A policeman who thought he spotted a marijuana plant in a resident's window got a shock when it turned out to be plastic - and crawling with little lizards.

Officer Claude Weinert first saw the plant in a second-floor window Monday when he was sent to the house in this south Chicago suburb to investigate a report of a fire.With help from narcotics officers, Weinert was shown how to take out a search warrant so he could enter the house Wednesday, officials said. It was his first drug raid.

"They came storming in here like a bunch of Gestapos acting like real idiots," said homeowner Ronald Gravelle, 46.

Two patrol officers and three plainclothes narcotics officers conducted the raid, only to come up with a plastic plant Gravelle's son, Joe, 18, bought as a home for his pet lizards.

Joe Gravelle and his girlfriend bought the plant three weeks ago to give a home to his seven lizards. "We just saw it at a yard sale and said, `What the heck,' " he said.

Police Chief Frank Gilbert said it was not easy to identify marijuana plants from far away and that mistaken searches happen.

"Until you get within one foot of it you cannot tell it from the real thing," Gilbert said. "(This) has never happened in my memory, and I've been here 30 years."

"This officer is taking a lot of razzing," said Capt. Robert Banas, who is in charge of the patrol division.

As for the fire report, it also turned out to be less serious than advertised: It was sticks burning on a backyard grill.