The Seattle Police Department announced Monday it would step up patrols in wake of bombings at the Boston Marathon.

New York, Los Angeles, Washington, D.C., and other major U.S. cities announced similar precautionary measures.

Seattle Police Chief John Diaz said the city has not received any threats in connection with Monday’s attack, but he urged citizens to be vigilant and report suspicious activity to 911.

“Our thoughts are with the people of Boston, the athletes participating in the Boston Marathon and their families,” the department said in a statement.

Assistant Chief Paul McDonagh, who commands the department’s Special Operations Bureau, said officers will focus their attention on major infrastructure and gathering areas across the city.

“Some of things that we’re doing you’re going to see, some of them you’re not going to see,” he said.

Seattle Mayor Mike McGinn also issued a statement Monday. He extended his condolences to victims of the attack and said the city will continue to monitor the situation.

Related:

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Photos from the scene in Boston