Islamic community leaders reacted with shock and grief after a Muslim couple apparently embarked on a deadly shooting rampage at a community center for people with developmental disabilities.

The Council on American–Islamic Relations — a nationwide advocacy organization — condemned the "horrific and revolting attack" in San Bernardino, California, and offered "heartfelt condolences" to families of the victims.

"The Muslim community stands shoulder to shoulder with our fellow Americans in repudiating any twisted mindset that would claim to justify such sickening acts of violence," Hussam Ayloush, the executive director of CAIR for the Los Angeles area, said in a statement.

Ayloush reacted within hours of the shooting at a Christmas party at a state-run center that killed 14. The alleged attackers, American-born Syed Rizwan Farook, 28, and wife Tashfeen Malik, 27, later died after police checking a lead in the nearby town of Redlands began chasing a vehicle believed to be related to the incident.

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The Islamic Community Center of Redlands said in a statement it was "saddened and shocked by the recent shooting in San Bernardino ... and prays for the victims and their family members."

"The center and its members offer their deepest condolences to those affected by this tragedy and we stand with our fellow Americans in this difficult time," the statement said, adding that it was planning an interfaith candlelight vigil for the victims.

Federal officials told NBC News that a check of customs and border protection records shows that Farook recently traveled to Saudi Arabia but authorities believe at this point that trip was purely a religious one — likely for the hajj, the pilgrimage that devout Muslims are required to at one point in their lives.”

Authorities would not rule out terrorism as a motive in the attack. Farook and Malik were wearing tactical gear and armed with assault-style rifles when they were killed, " San Bernardino Police Chief Jarrod Burguan told reporters Wednesday night, adding "there had to be some degree of planning."

Authorities also said an "explosive device" was found inside the building during a secondary sweep.