President Barack Obama on Wednesday urged the Sri Lankan government to end the violence and reduce civilian suffering in the country's long-running civil war. Obama called on the government to “stop the indiscriminate shelling” that has killed hundreds of civilians trapped in a narrow “safe zone” between government forces and Tamil Tiger rebels, and urged it to allow U.N. humanitarian teams access to civilians. The U.S. president, speaking to reporters on the White House lawn, also called on the Tamil Tigers to quit fighting and release civilian captives, saying the situation is a humanitarian crisis that could become a catastrophe. Doctors in Sri Lanka say last weekend's violence alone may have killed 1,000 people.