WASHINGTON - Police in Albuquerque, a city in the southern US state of New Mexico, Tuesday announced the arrest of an Afghan Muslim as the “primary suspect” in the killings of four Muslims, three of them from Pakistan, that raised fears in the community and led to increased security at mosques and schools, according to media reports.

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

The four shot dead last week, are: Naeem Hussain, Muhammad Afzaal Hussain and Aftab Hussain from Pakistan, while the fourth -- Mohammad Ahmadi -- was an Afghan.

The ambush-style killings drew a strong condemnation from President Joe Biden. Ahmad Assed, the president of the Islamic Center of New Mexico, a mosque that at least three of the victims had attended, said the authorities were looking at the possibility of sectarian killing to which the Afghan was apparently motivated.

Police officials said they were not yet sure but had found evidence that an “interpersonal conflict” may have led to the shootings.

The chief of the Albuquerque Police Department, Harold Medina, said that it was not yet appropriate to label the killings as either hate crimes or serial murders.

Syed had immigrated from Afghanistan and lived in Albuquerque for five or six years, according to the reports. He had faced several domestic violence charges in recent years that were later dismissed. Syed’s sons were questioned after his arrest and later released, the reports added. Several hundred people attended a vigil for the victims at the mosque on Tuesday evening. Muslim leaders, as well as Roman Catholic, Jewish, Sikh and Mennonite residents spoke about the losses absorbed by Albuquerque’s Muslim community. “The last two weeks have been nothing but nightmares,” Tahir Gauba, a director of the mosque, said. Referring to the arrest of the suspect, he added, “Tonight the Muslim community will sleep in peace.’ New Mexico Governor Michelle Lujan Grisham, a Democrat, said the arrest shows “law enforcement and all partners at their best,” while she thanked the public for providing tips. Grisham said state authorities would bring justice for the community.

“We are working on the justice side of that equation, which is absolutely critical,” the governor said at the press conference.

“We will bring justice, the full force of the law, and accountability will be made.” Last week police offered a $20,000 reward for information that led to the arrest of the suspect or suspects connected to the slayings. Albuquerque Police Department Deputy Commander Kyle Hartsock was quoted as saying that “hundreds” of tips came in from residents, leading police to the local residence of Syed, the suspect.