A bomb went off outside a Pakistan Navy office in the southern port city of Karachi today, killing at least one person and injuring three others. The bomb was hidden in a motorcycle that was in a parking area for two-wheelers outside the office at the Naval Colony in Baldia Town area. Police officials said that the identity of the dead and injured could not immediately be ascertained. Two suspects were arrested soon after the blast. Personnel from the navy and Pakistan Rangers cordoned off the site after the blast and launched an investigation. Ambulances rushed the injured to nearby hospitals. No group claimed responsibility for the attack.