SAN BERNARDINO (CBSLA.com) — Around 600 Inland Regional Center employees returned to work Monday for the first time since the deadly shooting massacre occurred in San Bernardino.

According to the IRC, employees gathered in small groups upon arriving to work this morning. Grief counselors were also on site in an effort to provide support.

READ MORE: Several Small Burbank Shops Targeted In Early Morning Burglary Spree

“It’s nice to be back and reconnect with everyone again,” IRC employee Don Meza said. “It’s nice to see their faces, to shake their hands and give them a hug.”

A security guard also checked identification cards of everyone who entered the building, located in the 1300 block of Waterman Avenue, to ensure safety.

The center has remained closed since Dec. 2, 2014, when Syed Rizwan Farook, 28, and his wife, Tashfeen Malik, 27, opened fire on dozens of San Bernardino County Health Department employees who were attending a holiday luncheon being held inside of a conference room at the IRC.

READ MORE: Kings Lose To Flames 3-2, Markstrom Makes 40 Saves

Fourteen people died and 22 others were injured.

The FBI has referred to the shooting massacre as being the deadliest attack on U.S. soil that has occurred since 9/11, CBS2’s Kara Finnstrom reported.

Later this afternoon, Gov. Jerry Brown is scheduled to attend a private memorial service in Ontario for the victims of the shooting.

MORE NEWS: Statements From Los Angeles Community College District and California Community Colleges Chancellor’s Office

The conference room building at the IRC will remain closed indefinitely.