Police in Albuquerque said they arrested the “primary suspect” in the killings of four Muslim men in New Mexico’s largest city – deaths that raised fears in the community and led to increased security at mosques and schools.

Muhammad Syed, 51, of Albuquerque, was charged in two of the killings and was called a suspect by police in the two other slayings. 

Chief Harold Medina said Tuesday the arrest happened after authorities tracked down a vehicle linked to one of the killings.

Authorities sought help Monday searching for a vehicle that appeared to be the one discovered Tuesday. Police said in a news release they suspected the vehicle was used in the homicides. 

The common elements in the deaths were the victims’ race and religion, officials said, and authorities discovered a possible link between the killings. Authorities released photos, hoping people could help identify the car, and offered a $20,000 reward for information leading to an arrest.

Mohammad Ahmadi, 62, from Afghanistan, was the first victim, killed Nov. 7. Aftab Hussein, 41, and Muhammad Afzaal Hussain, 27, were killed July 26 and Aug. 1, and Naeem Hussain, 25, was shot to death Friday, according to investigators. The last three victims were from Pakistan. 

Syed faces murder charges in the deaths of Muhammad Afzaal Hussain and Aftab Hussein. According to Deputy Commander Kyle Hartsock, Syed is suspected of “involvement” in the two other deaths. 

Hartsock said firearms found in Syed’s home and car through search warrants were matched to bullet casings at two crime scenes. 

‘Interpersonal conflict’ may be involved

Syed had a “possible personal relationship” with the first victim who was killed in November, Mohammad Ahmadi, Hartsock said. Syed has not been charged in connection with Ahmadi’s death, but remains a primary suspect, Hartsock said.