Police say they have uncovered a stash of guns, pipe bombs and explosives linked to Irish Republican Army dissidents.

The Police Service of Northern Ireland says the cache was discovered in woods near Lurgan, 20 miles (32 kilometers) southwest of Belfast.

Detective Supt. Karen Baxter said Friday that the items were in an advanced stage of readiness and included a "fully constructed explosive device."

The dominant IRA faction renounced violence in 2005, but breakaway groups still plot bombings and shootings in hopes of destabilizing Northern Ireland's peace process and Catholic-Protestant unity government.

In May the U.K. government raised the threat of a Northern Ireland-linked attack in mainland Britain to "substantial," meaning it's a strong possibility. In Northern Ireland it's a rung higher at "severe," meaning an attack is highly likely.