PORTLAND — Members of Occupy Maine reported a relatively peaceful evening, two days after someone heaved a chemical bomb into the midst of the Lincoln Park encampment, but there was one arrest.

Portland police arrested one man on a charge of disorderly conduct after one of the protesters, who was elected to head security, asked police for help.

The man appeared intoxicated and was being loud and disruptive, police said. He was warned once and when his behavior continued, he was charged with disorderly conduct, police said.

Police charged Nicholas Michael, 22, with disorderly conduct and he was taken to Cumberland County Jail. Occupy Maine protesters had asked him to move his tent away from their tents after he began yelling and swearing, police said.

Meanwhile, police continue to search for the people responsible for throwing the chemical device into the camp. Nobody was injured but the device created a loud noise and lots of smoke, protesters said.

Police have been searching for security video from area businesses that might show the older model silver compact car that witnesses believe was responsible for throwing the device. Police have not made an arrest yet.

Occupy Maine, which is protesting what participants see as favorable treatment for corporations at the expense of working people and the unemployed, was not the sole target of those responsible for the device, police said. Officers reported hearing a similar device explode about an hour before the incident in the park, somewhere southwest of the park.

Jason Lamy, a who was working security at 4 a.m. Sunday morning when the device was thrown, was at the opposite side of the park when it exploded.

Lamy said he had heard another explosion some time earlier. He thought the first noise came from the area of Oxford Street and later assumed the culprits had been practicing before tossing the Gatorade bottle filled with chemicals into the park.

Police were unable to locate the other device.