Leavenworth ? At least one man was killed Tuesday in a fire and explosion at a residence that authorities said housed a methamphetamine laboratory.

Rescue workers had not been able to search the home for other potential victims before calling off their work for the night.

Maj. Patrick Kitchens, a police spokesman, said the rescue effort was hampered by the discovery of a pipe bomb – about 18 inches long and 2 inches in diameter – that forced evacuations of nearby residents.

“The combination of circumstances makes this about as dangerous a circumstance as you can have,” Kitchens said.

Emergency officials were called about 3:50 a.m. with the report of the blaze at the single-family rental home. It was under control by about 5 a.m.

Fire Chief John Scanlon said the explosion was fairly small, blowing out a window and part of a wall, but the fire caused a portion of the roof to collapse.

Authorities removed the body of one victim from the scene but did not identify him. An autopsy was scheduled for today.

Investigators said they found chemicals and cooking tools that suggested a methamphetamine lab had been in operation. A bomb robot removed the explosive device.

The search for more possible victims and additional bombs was to continue today.