Police in the United States on Tuesday charged an Afghan man with murder after identifying him as the prime suspect in the murder of at least two of four men in Albuquerque, New Mexico. 

The suspect, Muhammad Syed, 51, who has lived in the US for five years, was arrested on suspicion of carrying out ambush shootings in the area against Muslim men. 

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 Syed, himself a Muslim, police said.

Local media reports indicate Syed, a Sunni, was angry about his daughter having married a Shiite. However, police have said they are investigating all possible motives.

Ahmad Assed, president of the Islamic Center 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 center’s mosque “from time to time.”

Naeem Hussain, a 25-year-old man from Pakistan, was killed 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, 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.