Hours before the Albuquerque killings suspect was publicly identified, CNN reporters were inside his home. Here's what happened - CNN

In the home, authorities found firearms, along with information showing Syed may have known the victims "to some extent" and interpersonal conflict may have led to the killings, police said Tuesday.

One of the firearms recovered in his home has been linked to bullet casings found at the scenes of two of the killings, while casings for a handgun found in his car when he was stopped were linked to one of the scenes, according to the arrest affidavit.

Police haven't yet determined a motive for the killings, they have said.

Syed denied any involvement in the killings during an interview with police on Tuesday, according to the arrest affidavit.

The daughter's husband was friends with two of the men who were killed, Aftab Hussein and Naeem Hussain, she told CNN, which has chosen not to name her out of concern for her safety.

Authorities, acting on a tip from the public, had been preparing to execute a search warrant on Syed's home Monday night when they saw him get into his car and followed him, deputy commander of the Albuquerque Police Department's Criminal Investigations Division Kyle Hartsock said in a Tuesday news conference.

Syed was pulled over and detained near Santa Rosa, New Mexico, about 120 miles east of Albuquerque and roughly halfway to the Texas border.

Meanwhile, police executed the search warrant in Syed's home and found multiple firearms, Hartsock said.