BBC: BP has managed to seal the smallest of the three leaks spilling oil into the Gulf of Mexico, the company says. Oil is still gushing into the sea at a rate of about 800,000 litres a day, but officials say working with only two leaks makes tackling the spill easier. Remote-controlled submarines are being used to guide a specially-constructed dome into place to try to stem the main leaks. Engineers plan to deploy the 100-tonne dome over the site on Thursday. BP has …