Prince George's County authorities seized two pipe bombs, several hundred pounds of explosive chemicals and powders, and other bomb-making paraphernalia yesterday in a rented, walk-in storage locker that an Oxon Hill man allegedly had been using as "a bomb factory," officials said.

Besides the two bombs and the bags and canisters of explosive substances, investigators found tools, pipes, tubes, fuses and an array of published bomb-making instructions in the 20-by-8-foot locker at U-Store on Livingston Road in Oxon Hill, officials said.

Fire Department spokesman Ron Siarnicki said investigators planned to seek an arrest warrant last night, charging the Oxon Hill man with numerous offenses, including manufacturing an explosive device, which is punishable by up to 20 years in prison and a $10,000 fine.

Siarnicki declined to identify the suspect before his arrest, describing him only as a man in his thirties who works at a Hechinger store in southern Prince George's.

Investigators have found no evidence linking him to any bombings, Siarnicki said.

He said the suspect allegedly brought handmade fireworks to the store several days ago and showed them to fellow employees. The man's supervisors confiscated the fireworks and gave them to fire officials, who began an investigation, Siarnicki said.

After obtaining a warrant, investigators searched his home Friday night and discovered more fireworks, but found no evidence that he was manufacturing them in his home, Siarnicki said. He said investigators obtained a warrant to search the storage locker after finding rental receipts in the man's home.

Each of the two bombs was two to three inches long, Siarnicki said. Each was a cast-iron pipe stuffed with an explosive mixture, capped at both ends and ready to be ignited by a fuse.

Siarnicki said investigators described the mixtures in the bombs as "unstable," particularly when left to sit in the locker, which is not air-conditioned. It was not clear last night how investigators disposed of the bombs.