ALEXANDRIA, Egypt — A powerful bomb exploded in front of a crowded Coptic Christian church a half hour into the New Year early Saturday, hitting worshipers emerging from a holiday Mass in the Egyptian city of Alexandria and killing at least 21 people in an attack that raised suspicions of an al-Qaida role.

A direct al-Qaida hand in the bombing would be a dramatic development, as Egypt's government has long denied that the terror network has a significant presence in the country.

WASHINGTON — Afghan President Hamid Karzai refused to remove a former warlord from atop the energy and water ministry despite U.S. pressure to oust the minister because Washington considered him corrupt and ineffective.Secret diplomatic records showed the minister — privately termed “the worst” by U.S. officials — kept his perch at an agency that controls $2 billion in U.S. and allied projects.The refusal to remove the official despite threats to end U.S. aid highlights how little influence the U.S. has over the Afghan leader on pressing issues such as corruption.