HONG KONG, July 8 (Xinhuanet) -- Security has been tightened in some Asian countries on Friday after a series of bomb attacks in London that killed at least 50 people and injuring some 700 others.

    South Korea tightened security measures over airports and other major facilities on Friday. Police raised terror alert and intensified baggage checks at the Incheon International Airport, the country's biggest gateway.

    The National Police Agency deployed armored vehicles, and sent bomb-sniffing dogs into Seoul Station in and near the American Embassy in the downtown area.

    South Korean Defense Minister Yoon Kwang-ung also instructed military bases at home and abroad to beef up their security measures.

    The nation's 3,600-strong military unit is the third largest presence of foreign troops in Iraq after the United States and Britain.

    "The South Korean military base in Iraq is on a 24-hour alert, and it has also mapped out measures to counter suicidal air attacks," Yoon was quoted by the Yonhap news agency as saying.

    A series of four coordinated blasts ripped through London's subway system and destroyed a double-decker bus, killing at least 50 people and leaving some 700 injured.

    An al-Qaida-linked group has claimed responsibility, saying that the attack was a retaliation for Britain's involvement in the US-led operations in Iraq and Afghanistan.

    Japan, a staunch ally of the United States and is deeply involved in the operations in Iraq and Afghanistan, also stepped up security measures Friday.

    Chief Cabinet Secretary Hiroyuki Hosoda, who is currently taking charge in the government as Prime Minister Junichiro Koizumi is attending the Group of Eight summit in Scotland, said Friday that he has asked government officials to beef up security.     

    National Public Safety Commission Chairman Yoshitaka Murata and transport minister Kazuo Kitagawa separately pledged to double vigilance against possible attacks on public transportation networks such as railways and other places, Hosoda said.

    Measures to be taken also include intensifying sea patrols by the Japan Coast Guard and the Maritime Self-Defense Force, tightening immigration scrutiny and increasing guards at crowded places such as the ongoing World Exposition in Aichi Prefecture, Defense Agency chief Yoshinori Ono said.

    In Tokyo, the Metropolitan Police Department has dispatched extra police officers at major train stations and high-profile embassies such as those of the United States and France.

    In Australia, security is being stepped up in major cities. As Australian experts warn people that an attack on Australian soil is inevitable, security was beefed up with increased patrols and surveillance of public transport system of Sydney, Australia's biggest city and capital of the state of New South Wales (NSW).

    NSW Premier Bob Carr said the attack served as a warning to Australia and that details of a city-wide evacuation plan, which is directed at dealing with an emergency akin to London's, would be announced next month.

    Police have intensified their presence at possible terrorist targets in the state of Queensland. Security has also been increased at main transport hub in Perth, capital of the state of Western Australia, with armed police officers being stationed at the city's central train station.

    The anti-terrorism arrangements for next year's Commonwealth Games in Melbourne, capital of the state of Victoria, are being reassessed in the wake of the bombings. Enditem