Arusha. At least 60 people were injured in an explosion at a church in Tanzanian northern city of Arusha that also left one worshiper dead, police has said.Authorities in Tanzania appealed for calm as security officials rushed to the northern city to start investigations into the blast.Shock and panic gripped the region following the attack which was executed as Vatican Ambassador to Tanzania Francisco Padilla, who was accompanied by Archbishop of Arusha Josphat Lebulu, was about to inaugurate a Catholic church at Olasiti on the outskirts of the normally serene city.The attack took place despite heavy security presence in the area.Police spokesperson Advera Senso declined to comment, saying it was too early to give any meaningful information about the incident."We appeal for calm and urge people to cooperate with the police. More information will be released in due course as we advance in our investigations. IGP Mwema has travelled to Arusha to oversee the investigations,” Ms Senso said when contacted for comment.For his part, Arusha Regional Police Commander Liberatus Sabbas said that a manhunt for the attackers was underway and one person has been questioned.Fear was rife in the city as news of the blast spread across the country.Eye witnesses said the attack took place at around 10:40am as parish members and other believers converged at the main door to witness the opening ceremony.Just as the Vatican envoy, who was the official guest, was about to cut the tape to let the believers get into the newly-completed church building, there was a huge explosion in the middle of the crowd.Mr Khalifa Mshana, a cameraman with the Tanzania Broadcasting Corporation (TBC), who was covering the function, said that the ‘bomb’ exploded only a few metres from the Vatican envoy.