A 51-year-old man from Afghanistan was charged Tuesday with killing two Muslim men in Albuquerque, N.M., authorities said, and he is suspected in the slayings of two others whose deaths sparked fear in Muslim communities nationwide.
Officials announced the arrest of Muhammad Syed a day after he was taken into custody.
Police Chief Harold Medina said authorities had tracked down a vehicle believed to be involved in one of the slayings in New Mexico's largest city.
"The driver was detained, and he is our primary suspect for the murders," a tweet said.
Investigators received tips from the city's Muslim community that pointed them toward Syed, who arrived in the U.S. sometime in the last several years, police said.
The motive and exact nature of the relationships between Syed and the victims -- and the victims to one another -- remained unclear. But police continued to investigate how they crossed paths before the shootings.
"Detectives discovered evidence that shows the offender knew the victims to some extent and an interpersonal conflict may have led to the shootings," police said.
The slayings drew the attention of President Joe Biden, who said such attacks "have no place in America." They also sent a shudder through Muslim communities, where some people questioned their safety and limited their movements.
When told about the announcement, Muhammad Imtiaz Hussain, the brother of one of the victims, Muhammad Afzaal Hussain, said he felt relieved but needed to know more about the suspect and the motive.
"This gives us hope that we will have [the] truth come out," he said. "We need to know why."
Naeem Hussain was killed Friday night, and the three other men died in ambush shootings. Three of the four slayings happened in the last two weeks.
Hussain, 25, was from Pakistan. His death came just days after those of Muhammad Afzaal Hussain, 27, and Aftab Hussein, 41, who were also from Pakistan and members of the same mosque.
The earliest case involves the November killing of Mohammad Ahmadi, 62, from Afghanistan.
For now, Syed was charged in the killings of Aftab Hussein and Muhammad Afzaal Hussain because bullet casings found at the crime scenes were linked to a gun found at his home, authorities said.
Investigators consider Syed to be the primary suspect in the deaths of Naeem Hussain and Mohammad Zaher Ahmadi but have not yet filed charges in those cases.
Police were about to search Syed's Albuquerque home Monday when they saw him drive away in a Volkswagen Jetta that investigators believe was used in at least one of the slayings.
Officers followed Syed to Santa Rosa, about 110 miles east of Albuquerque, where they pulled him over in a traffic stop. Multiple firearms were recovered from his home and car, police said.
Syed's sons were questioned and released, authorities said.
Aneela Abad, general secretary at the Islamic Center of New Mexico, described a community reeling from the killings, its grief compounded by confusion and fear of what may follow.
"We are just completely shocked and still trying to comprehend and understand what happened, how and why," she said.
Some people have avoided going out unless "absolutely necessary," and some Muslim university students have been wondering whether it is safe for them to stay in the city, she said. The center has also beefed up its security.
Few anti-Muslim hate crimes have been recorded in Albuquerque over the last five years, according to FBI data cited by Brian Levin, director of the Center for the Study of Hate and Extremism and a professor of criminal justice at California State University at San Bernardino.
From 2017 through 2020, there was one anti-Muslim hate crime a year. The highest recent number was in 2016, when Albuquerque police recorded six out of a total of 25 hate crimes.
Information for this article was contributed by Lindsay Whitehurst, Rhonda Shafner and Jennifer Farrar of The Associated Press.
This undated photo released by the City of Española shows Muhammad Afzaal Hussain, 27, a planning and land use director who was killed in Albuquerque, N.M., on Aug. 1, 2022. Hussain is one of four victims in a series of killings of Muslim men in New Mexico's largest city as the deaths sent ripples of fear through the religious community nationwide. (City of Española via AP)
Altaf Hussain cries over the grave of his brother Aftab Hussein at Fairview Memorial Park in Albuquerque, N.M., on Friday, Aug. 5, 2022. A funeral service was held for Aftab Hussein, 41, and Muhammad Afzaal Hussain, 27, at the Islamic Center of New Mexico on Friday. Both Muslim men were shot and killed near their homes only six days apart. Law enforcement believes one suspect could be responsible for killing three Muslim men in the past nine months. (Chancey Bush/The Albuquerque Journal via AP)
People sprinkle dirt over the grave of Muhammad Afzaal Hussain, 27, at Fairview Memorial Park in Albuquerque, N.M., on Friday, Aug. 5, 2022. A funeral service was held for Aftab Hussein, 41, and Muhammad Afzaal Hussain, 27, at the Islamic Center of New Mexico on Friday. Both Muslim men were shot and killed near their homes only six days apart. Law enforcement believes one suspect could be responsible for killing three Muslim men in the past nine months. (Chancey Bush/The Albuquerque Journal via AP)
Albuquerque Police Deputy Chief of Investigations Cecily Barker holds a flyer with photos of a car wanted in connection with Muslim men murdered as Governor Michelle Lujan Grisham looks on in Albuquerque, New Mexico, Sunday, Aug. 7, 2022. Authorities investigating the killings of four Muslim men said they are looking for help finding a vehicle believed to be connected to the deaths in New Mexico's largest city. A Muslim man was killed Friday, Aug. 5, 2022, in Albuquerque, and ambush shootings killed three other Muslim men over the past nine months. (Adolphe Pierre-Louis/Albuquerque Journal via AP)
An Imam leads a group of men during the Dhuhr afternoon prayer at the Islamic Center of New Mexico in Albuquerque, New Mexico, Sunday, Aug. 7, 2022, after the fourth Muslim man was murdered in the city. Authorities investigating the killings of four Muslim men said they are looking for help finding a vehicle believed to be connected to the deaths in New Mexico's largest city. A Muslim man was killed Friday, Aug. 5, 2022, in Albuquerque, and ambush shootings killed three other Muslim men over the past nine months. (Adolphe Pierre-Louis/Albuquerque Journal via AP)
People spread dirt over Aftab Hussein's grave at Fairview Memorial Park in Albuquerque, N.M., on Friday, Aug. 5, 2022. A funeral service was held for Aftab Hussein, 41, and Muhammad Afzaal Hussain, 27, at the Islamic Center of New Mexico on Friday. Both Muslim men were shot and killed near their homes only six days apart. Law enforcement believes one suspect could be responsible for killing three Muslim men in the past nine months. (Chancey Bush/The Albuquerque Journal via AP)
Ahmad Assed, president of the Islamic Center of New Mexico, speaks during a news conference to address the killing of a fourth Muslim man that happened early Saturday, Aug. 6, 2022, in Albuquerque, N.M., during a news conference. (Chancey Bush/The Albuquerque Journal via AP)
Altaf Hussain cries over the grave of his brother Aftab Hussein at Fairview Memorial Park in Albuquerque, N.M., on Friday, Aug. 5, 2022. A funeral service was held for Aftab Hussein, 41, and Muhammad Afzaal Hussain, 27, at the Islamic Center of New Mexico on Friday. Both Muslim men were shot and killed near their homes only six days apart. Law enforcement believes one suspect could be responsible for killing three Muslim men in the past nine months. (Chancey Bush/The Albuquerque Journal via AP)
A young man bows during the Dhuhr afternoon prayer at the Islamic Center of New Mexico, Sunday Aug. 7, 2022, after the fourth Muslim man was murdered in Albuquerque. (Adolphe Pierre-Louis/The Albuquerque Journal via AP)