An explosion of a boiler's steam line at the Aldrich Chemical Co. killed two maintenance workers early Monday, officials said.

The blast at about 12:45 a.m. damaged one of several buildings at the plant in the town of Wilson, about 25 miles north of Milwaukee, said Capt. Steve Dortman of the Sheboygan County Sheriff's Department."It didn't involve any chemicals, which were located elsewhere," he said.

A 37-year-old man was pronounced dead after being taken to St. Nicholas Hospital at Sheboygan, Dortman said. A 25-year-old man injured in the explosion died several hours later at Memorial Medical Center in Sheboygan, the captain said.

The names of the victims were not immediately released, pending notification of relatives.