A single shot was fired through the window of President Barack Obama’s Denver campaign office Friday, according to police.

Police spokeswoman Raquel Lopez says people were inside the office when the shooting happened in the afternoon, but no one was injured.

A large panel of glass was left shattered at the office on West Ninth Avenue near Acoma Street.

Raquel Lopez says investigators are looking at surveillance video but have not yet confirmed a description of a vehicle that might be linked to the shooting. Police didn’t immediately release other details while detectives pursue leads.

She says she isn’t aware of any previous threats against the campaign office.

A large panel of glass was left shattered at Barack Obama’s campaign office on West Ninth Avenue near Acoma Street in Denver

The incident happened at around 3:00 p.m., according to The Denver Post. Sam Levin, a reporter for the alternative newspaper Westword, later posted a photo on Twitter showing one of the office’s large, front windows shattered.

By early evening, the window shards had been removed and a glass company was putting plywood up.

The Secret Service referred questions about the incident to Denver police.

An Obama campaign spokeswoman declined to comment.

Politico reported that the president’s re-election campaign has more than 30 field offices across all of Colorado – a major battleground state in advance of the November 6 election.

Denver was also the site of the first presidential debate between Mitt Romney and President Barack Obama.

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