By GREGORY KATZ A British-flagged cargo ship and a chemical tanker from Singapore have both been hijacked by pirates in the perilous waters off the coast of Somalia, officials said Saturday.The Asian Glory highjacking happened late Friday roughly 600 miles (1,000 kilometers) east of Somalia, said Commander John Harbour, a spokesman with the European Union task force charged with combating piracy off Somalia.That same day, the Singaporean-flagged Pramoni, a chemical tanker with a crew of 24, was seized by pirates in the Gulf of Aden, one of the world's busiest waterways.Harbour said the Asian Glory's crew of 25 appeared to be safe and that the pirates had not yet made contact with the ship's owner, Zodiac Management Agencies."The standard procedure for the pirates is to get the ship back to their stronghold and then contact the owner," he said.