SEATTLE - Emergency teams rushed to a Seattle hotel and some guests thought they were under attack when a chemical irritant was released into the ventilation system Sunday morning.

Dozens of police, hazmat teams and medics were dispatched to the scene, the Hotel Andra at Fourth Avenue and Virginia Street, at about 11:15 a.m.

Meanwhile, guests tried to escape from the chemical, which burned their throats and eyes.

"I started coughing - my wife started coughing," said Pete Naumovski, who was staying at the hotel. He said he wondered, "Is this some sort of terrorist thing or something bigger going on?"

At first he and several other guests raced to the roof. But the fumes were just as bad there, so they went downstairs to the lobby.

"We were kind of sitting there - dead ducks, so to speak - thinking how are we going to get out of here?" he said.

Another guest, Zlata Naumovski, was caught in the fumes in her room on the fifth floor.

"I opened the door to get some more air and it was actually worse," she said. "Somebody from the hotel told us to get out."

The entire fifth floor of the hotel was evacuated.

Outside, firefighters blocked off the whole area as medics treated people in the middle of Fourth Avenue. Five victims were treated at the scene for their symptoms. No one was hospitalized.

The chemical irritant turned out to be bear-strength pepper spray.

Firefighters said a maid accidentally knocked over a large pepper spray can - the kind used to fight off bears - as she was cleaning a room. The fumes quickly spread through the hotel's ventilation system.

Investigators say they don't know who the pepper spray belonged to or why it was inside the room.

Once the hotel was aired out, all guests were able to return to their rooms.

"There were no injuries, and we anticipate no need to relocate any of our guests," the hotel management said in a statement.