Suspected Tamil Tiger rebels ambushed and killed three soldiers in Sri Lanka's restive east on Monday, as a Norwegian peace broker flew in to begin a last-ditch bid to avert a slide back into civil war. The patrol was ambushed with a deadly claymore fragmentation mine, a block of plastic explosive which blasts out ball bearings. It was the latest in a string of deadly attacks that have killed over 70 armed forces personnel since December. In a separate ambush, suspected rebels shot and wounded four anti-terrorist police in the neighboring eastern district of Ampara, while a rebel supporter was shot dead in the northern army-held Jaffna peninsula. The attacks came just hours after peace envoy Erik Solheim touched down in Sri Lanka for a three-day visit to try to convince the government and the rebels to agree on a venue for talks to haul a 2002 truce back from breaking point. U.S. Undersecretary of State Nicholas Burns was also in Sri Lanka on Monday for talks with Solheim and officials, while London-based chief Tiger negotiator Anton Balasingham flew to the northern rebel stronghold of Kilinochchi, according to a report of Reuters.