Jarrod Burguan, San Bernardino police chief

Fifteen pipe bombs and thousands of rounds of ammunition were recovered by authorities investigating the husband and wife team who stormed a workplace holiday party in a San Bernardino and opened fire, killing 14 people and injuring 21, officials said Thursday.

The Washington Times reported that investigators found many of the items during a search of a residence that was rented by the two suspects, 28-year-old Syed R. Farook and 27-year-old Tashfeen Malik, who were both killed in a firefight with police as they fled the home.

Syed Rizwan Farook: the face of the shooter

Between 65 and 75 firearms casings were recovered at the regional centre along with three pipe bombs that were conjoined together as one explosive device.

“They sprayed the room with bullets, I don’t know that there was any one person they targeted,” the chief said.

It remained unclear whether a county government holiday party at the Inland Regional Centre was the target of the attack, or if the suspects had additional plans.

“We don’t know if this was the intended target or if there was something that triggered him to do this immediately,” said David Bowdich, assistant director in charge of the FBI’s Los Angeles field office.

Inside the home rented by the couple, officials found 12 explosive devices, additional bomb making materials, and more than 4,500 rounds of ammunition for various firearms.

“This is not your average investigation,” FBI David Bowdich said mentioning the multiple crime scenes, victims and recovered evidence. “It will take time.”

At Thursday’s press conference, officials also released a few new details about the suspects – including that Mr. Farook, a U.S. citizen, had travelled to Pakistan and returned to the U.S. in July 2014. Ms. Malik had come to the U.S. on a visa from Pakistan with him.

On a dating website, Farook included in his profile that he loved target shooting practice with his sister.

Farook, who was born in Chicago, hinted at his religious background on the dating profile on the site iMilap.com published several years ago, according to dailycaller.com

In a short narrative, he described himself as hailing from a “religios [sic] but modern family of 4, 2 girls 2 boys.”

“I work for county as health, safety and envorimental [sic] inspector. Enjoy working on vintage and modern cars, read religios books, enjoy eating out sometimes travel and just hang out in back yard doing target practice with younger sister and friends.”

Farook is also listed as a 2009 graduate of California State University, San Bernardino, where he received a Bachelor’s of Science in Environmental Health. He has worked as an environmental health specialist for San Bernardino County for the past five years.