Pasco County sheriff's deputies called in the SWAT team after trying to serve a search warrant Thursday morning at the trailer, sheriff's spokesman Doug Tobin said. He said authorities believed a man armed with a shotgun was barricaded inside.
"There has been a history of neo-Nazi activity in the neighborhood, but no clear evidence this is related to the stabbing," Tobin said in a statement.
A 45-year-old woman and a 17-year-old boy were stabbed at the home shortly after midnight, authorities said. The victims, whose names were not released, were taken to a hospital, and at least one was seriously injured.
Both victims were stabbed multiple times by a masked man, the sheriff's office said. The woman was stabbed first, but was able to seek help from a neighbor. The boy was apparently stabbed while trying to escape the trailer.
New Port Richey is about 40 miles northwest of Tampa.