(KRON) — A suspicious package containing a powdery substance sent to a Council on American-Islamic Relations office in Santa Clara has led to an evacuation this afternoon, according to the advocacy group’s regional executive director.

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Employees at a Council on American-Islamic Relations office in Santa Clara were taken to a hospital for evaluation as a precaution after they received an envelope containing a suspicious powdery substance, according to the advocacy group’s Bay Area executive director.

But CAIR wrote on Facebook just after 9 p.m. Thursday that the staff who was taken to the hospital has been released. The building, however, remains closed, CAIR said.

Update: the three CAIR-SFBA staff who were taken to the hospital have been released. The building however remains closed.Posted by CAIR on Thursday, December 10, 2015

Everyone inside CAIR’s office and other businesses at the two-story building at 3000 Scott Blvd. was evacuated as of 2:30 p.m., said Zahra Billoo, executive director of the Bay Area chapter of CAIR. Billoo said she was not at the office this afternoon.

CAIR workers notified police and the FBI soon after the discovery, she said. A HazMat crew is on the scene.

Billoo said there are raised concerns about the suspicious package because of a similar incident that happened at the council’s national office in Washington, D.C.

The national office received a letter containing a “foreign substance” in the mail earlier today, the organization said on Twitter.

Preliminary tests of the substance sent to the Washington office showed it was not dangerous and the FBI now has possession of the letter, which they will continue to test, the organization said on Twitter.

Brice Hamack, CAIR’s Northern California civil rights coordinator, said he was one of three people at the Santa Clara office when they found the substance.

Hamack said he was outside of the building as of around 2:30 p.m. and did not know of any injuries reported.

As of 6 p.m., the suspect remains unidentified and the building was being decontaminated, according to Zahra Billoo, executive director of the Bay Area chapter of CAIR, who said she was not at the office Thursday afternoon.

Billoo said there are raised concerns about the suspicious package because of a similar incident that happened at the council’s national office in Washington, D.C.

The national office received a letter containing a “foreign substance” in the mail earlier today, the organization said on Twitter.

Preliminary tests of the substance sent to the Washington office showed it was not dangerous and the FBI now has possession of the letter, which they will continue to test, the organization said on Twitter.

Brice Hamack, CAIR’s Northern California civil rights coordinator, said he was one of three people in the Santa Clara office when they found the substance.

Police said traffic is moving slowly in the area due to the incident and the weather, and drivers are being asked to avoid the area.

Emergency responders are expected to remain on scene for a few more hours this evening, officials said.Bay City News contributed to this report.

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