SAN BERNARDINO, Calif. -- The FBI has not said what it was looking for in a raid early Saturday at the home next door to where San Bernardino shooter Syed Farook's family used to live in Riverside, California.
Neighbors say authorities with guns drawn broke windows and used a cutting torch to get into the garage. A neighbor says an old friend of Farook's is the person that lives in the house.
A law enforcement official says that more than three years ago, that person bought two assault rifles later used in the shooting, but authorities haven't been able to talk to him because he checked himself into a mental hospital after the attack. The official was not allowed to discuss the investigation publicly and spoke on condition of anonymity.
VIDEO: Woman at center of FBI investigation of San Bernardino attack
The FBI has said the man is not a suspect in shootings, though they want to question him.
Meanwhile, the White House says President Barack Obama will address the nation from the Oval Office at 8 p.m. Eastern Time on Sunday about the steps the government is taking to keep people safe after the attack this past week in California.
Obama will provide an update on the San Bernardino attack that killed 14 and wounded 21 and will also discuss the broader threat of terrorism. He will talk about the nature of the threat, how it has evolved, and how he plans to defeat it.
He will talk about his determination that the Islamic State group must be destroyed. And he will make the case that the United States must draw the nation's values - its commitment to justice, equality and freedom - to prevail over terrorist groups.
The latest on the mass shooting in San Bernardino, California (all times local):
Neighbors say authorities have raided a home next door to the house where the family of shooter Syed Farook used to live in Riverside, California.
Maria Gutierrez says she was told to leave her house further down the street at 1:30 a.m. Saturday for safety reasons as authorities swept in with guns drawn.
She says authorities used a megaphone to tell whoever was in the house to come out.
Another neighbor, Lorena Aguirre, says law enforcement broke windows and used a torch to get in the garage.
FBI spokeswoman Laura Eimiller says agents served a federal search warrant at the house overnight. She declined to discuss what they were looking for.
Authorities say Farook and his wife Tashfeen Malik killed 14 people in a rampage in San Bernardino, California.
President Barack Obama and French President Francois Hollande are stressing cooperation between their governments and with their allies to wipe out terrorism.
The White House says the renewed pledges of cooperation were made Saturday as the leaders discussed the California shootings by telephone.
Obama accepted condolences Hollande offered to the U.S. public.
Just three weeks ago, Obama telephoned Hollande to offer his condolences after a series of gun-and-bomb attacks across Paris left 130 people dead and hundreds wounded. The Islamic State group has claimed responsibility for the Nov. 13 attacks.
Authorities say the husband-and-wife shooters who killed 14 people at a county government building in San Bernardino, California, this week were possibly self-radicalized but not part of a broader terrorist network.
Obama also briefed Hollande on the investigation into the shootings.
President Barack Obama says this week's deadly California shootings were "an act of terror" carried out by attackers who were possibly radicalized to commit it.
The president's comments came during his weekly radio and Internet address Saturday, a day after the FBI said it was investigating Wednesday's shootings as "an act of terrorism."
Obama says proven radicalization would underscore the threat posed by people who give in to violent extremist ideologies.
FBI Director James Comey (KOH'-mee) said evidence thus far indicates the shooters showed signs of radicalization but were not part of a broader terrorist network.
Several Republican presidential candidates had quickly labeled the shootings an act of terrorism and faulted Obama for not saying so immediately.
On Thursday, as investigators were searching for a motive, Obama said at the White House that the shootings could have been terrorist-related or workplace-related.
In Pakistan, a relative of female shooter Tashfeen Malik says the woman apparently became a more zealous follower of the Muslim faith about three years ago.
Hifza Batool tells The Associated Press on Saturday other relatives have said that Malik, who was her step-niece, used to wear Western clothes but began wearing the hijab head covering or the all-covering burqa donned by the most conservative Muslim women about three years ago.
"I recently heard it from relatives that she has become a religious person and she often tells people to live according to the teachings of Islam," said Batool, 35, a private school teacher who lives in Karor Lal Esam, about 450 kilometers (280 miles) southwest of the Pakistani capital of Islamabad.
Batool said she had never met Malik, who mostly grew up in Saudi Arabia with her family. Batool said the two families were not on speaking terms.
"Tashfreen Malik's parents are rich and we are poor and they don't like to meet with their poor relatives," she said.
- Associated Press writer Asim Tanveer in Karor Lal Esam, Pakistan
The Islamic State group's official radio station has aired a statement saying the mass shooting in California was carried out by two "supporters" of the extremist group.
While praising the attack, the group stopped short of claiming responsibility for it. The Al-Bayan report Saturday echoed a claim carried Friday by the IS-affiliated Aamaq news agency.
The radio report did not refer to Syed Farook and Tashfeen Malik as actual members of the Islamic State group. Militants affiliated with IS who carry out attacks are commonly referred to in the group's propaganda as "lions," ''fighters" or "mujahedeen."
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Police suspect neighbor bought weapons used in San Bernardino attack
SAN BERNARDINO MASS SHOOTING