New Mexico police announced a breakthrough on Tuesday in the killings of four Muslim men in Albuquerque, charging a man from Afghanistan — himself a Muslim — with two of the slayings.

Muhammad Syed, 51, was also identified as a prime suspect in the other killings that put the entire community on edge.

He was taken into custody on Monday after a traffic stop more than 100 miles away, authorities said.

Three of the four ambush shootings happened in the last two weeks. Police Chief Harold Medina said it was not clear yet whether the deaths should be classified as hate crimes or serial killings or both.

Investigators received a tip from the city’s Muslim community that pointed toward Mr Syed, who has lived in the US for about five years, police said.

Police were looking into possible motives, including an unspecified “interpersonal conflict”.

When asked specifically if Mr Syed, a Sunni Muslim, was angry that his daughter married a Shiite Muslim, deputy police commander Kyle Hartsock did not respond directly. He said “motives are still being explored fully to understand what they are”.

Ahmad Assed, president of the Islamic Centre of New Mexico, acknowledged that “there was a marriage”, but he cautioned against coming to any conclusions about the motivation of the suspect, who he said attended the centre’s mosque “from time to time”.

The exact nature of the relationships between Mr Syed and the victims – and the victims to one another – remained unclear. But police said they continue to investigate how they crossed paths before the shootings.

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 across the US. Some people questioned their safety and limited their movements.

Naeem Hussain, a 25-year-old man from Pakistan, was killed on Friday night. 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, Mr Syed is 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 Mr Syed to be the primary suspect in the deaths of Naeem Hussain and Ahmadi but have not yet filed charges in those cases.

Police said they were about to search Mr Syed’s Albuquerque home on 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 him to Santa Rosa, about 110 miles east of Albuquerque, where they pulled him over. Multiple firearms were recovered from his home and car, police said.