Two grenades hurled at a restaurant in the northeastern Kenyan town of Wajir, near the border with Somalia, wounded five people on Wednesday, provincial officials and residents said, in the latest in a spate of attacks in the region.Kenya has been hit by a series of grenade and bomb blasts since its troops crossed into Somalia in October to fight Islamist militants.Nairobi has blamed Somalia’s al Shabaab, a movement linked to al Qaeda. The attackers have targeted Kenya’s northeast, the capital and the port city of Mombasa, threatening the country’s lucrative tourism sector."I heard two blasts and people screaming behind my house,” Ibrahim, a resident in the neighbourhood, told Reuters.Five people were wounded and some were being treated at the district hospital, provincial medical officer Abdikader Sheikh said."No deaths have been reported, only cases of injuries from a twin explosive attack,” he added.Three Kenyan police officers were killed in an ambush in the northeastern border town of Liboi on Monday.Al Shabaab merged with al Qaeda this year and has declared war on Kenya because of its incursion into Somalia.