More than 12 people were injured yesterday when a car bomb exploded outside a church in Karachi. Television footage of the blast at Holy Trinity Anglican Cathedral showed extensive damage to cars in the area, with twisted metal and shattered glass scattered over the street. The explosion is the first attack on Pakistan's small Christian community for more than a year. In 2002, six attacks on Christian targets left more than 40 people dead. Most of the attacks were blamed on Islamic militants angry at Pakistan's support for the American-led 'war on terrorism'. The killings prompted calls for better security and protection at Christian buildings. In mainly Muslim Pakistan there are only 3.8 million Christians - about 2.5% of the national population. Built in 1855, Holy Trinity Anglican Cathedral is the oldest Protestant church in the city. The tower was used in the past as a beacon, clearly visible to ships approaching Karachi harbour.