WORLD IN BRIEF: Queen makes visit to Canada

TORONTO -- Queen Elizabeth II and Prince Philip arrived in Canada on Monday for the start of a nine-day tour of a country she calls a second home.

The queen, wearing a yellow hat and a raincoat over her yellow suit, was officially welcomed to Halifax, Nova Scotia, by Canadian Prime Minister Stephen Harper and hundreds of Canadians who stood in a steady rain to get a glimpse.

The queen is the symbolic head of state in Canada, a member of the British Commonwealth of former colonies. She last visited Canada in 2005.

On Canada Day, she will be on Parliament Hill in Ottawa for celebrations of the country's 143rd birthday. She visiting in part to mark the Canadian navy's centennial.

Truck blast kills 18 in Pakistan

KARACHI, Pakistan -- A truck carrying chemicals accidentally exploded Monday in southern Pakistan after pressure built up in its storage tank, killing 18 people and wounding 40, police said.

Hundreds of people rushed to the truck depot in Hyderabad city to search through the rubble of destroyed shops for dead and wounded, local television footage showed.

Authorities ruled out terrorism and determined the blast occurred from a pressure buildup, said Mohammad Ali Baloch, the senior police official in Hyderabad.

The truck was carrying 7,925 gallons of ''thinner,'' said Babar Khattak, the police chief in Sindh province where Hyderabad is located. He was not more specific about the chemical being transported.

US: Ship sinking not terrorism

WASHINGTON -- The Obama administration said Monday that the sinking of a South Korean warship blamed on North Korea was not terrorism, and not enough by itself to put Pyongyang back on a U.S. terror blacklist.

The State Department said the March sinking of the South Korean frigate Cheonan by a reported torpedo from a North Korean submarine was a ''provocative action'' and a violation of the truce that ended the Korean war.

But it added that the sinking was the act of one state's military against another and not an act of terrorism. Thus, it is not grounds to put North Korea back on the U.S. ''state sponsors of terrorism'' list as some in South Korea had wanted, spokesman P.J. Crowley said.

The North had been on the terror list but was removed in 2008 amid progress in the now-stalled effort to get it to abandon nuclear weapons.

The sinking ''was a provocative action but one taken by the military of a state against the military of another state,'' Crowley said. ''That in our view does not constitute and act of international terrorism.''