PORTLAND — An Alfred man accused of having bombs and growing marijuana pleaded guilty in U.S. District Court today to four of the five the charges against him.

Robert Infante, 47, entered conditional guilty pleas to charges of possession of firearms and ammunition by a felon; possession of an unregistered destructive device; manufacturing marijuana; and possession of a destructive device in relation to drug trafficking.

The conditional nature of the pleas allow Infante to appeal decisions that allowed evidence from a search of his home and a statement to authorities to be considered in his case.

Infante could face 45 years to life in prison. A date for the sentencing hearing has not yet been set.

On June 25, 2010, Infante called 911 and said he needed an ambulance because a small propane tank had exploded, according to court documents. He left for the hospital when he got tired of waiting. He did pull over on the way and allow rescue workers to treat his left hand before continuing on himself.

Firefighters searched Infante’s home to see if there was any more danger. They found more than a dozen pipe bombs, materials for making others and 200 marijuana plants.

Authorities later found two handguns and ammunition in the house. Police say they seized five pipe bombs from Infante’s car at the  hospital.

Infante did not change his not guilty plea for the fifth charge: possession of a firearm in relation to drug trafficking. Assistant U.S. Attorney Stacey Neumann said the government was not inclined to pursue the charge, given Infante’s guilty pleas for the others, and planned to ask for it to be dismissed.

In 1989, Infante was convicted in Vermont on federal charges of possession and manufacture of a destructive device. He was convicted of being a felon in possession of a firearm in 1993.