Security Tightened in Two Iraqi Christian Areas

Iraqi security forces have imposed curfews and vehicle bans in two mostly Christian towns, a day after bombings at churches in Baghdad killed four people and wounded 18 others.

Security forces imposed curfews Monday in Tilkaif and Hamdaniya, predominantly Christian towns near Mosul. Authorities also raised security around churches in Baghdad.

Bombs exploded outside several Christian churches in the capital Sunday, killing four people near one church in eastern Baghdad.

Islamist militants have staged sporadic attacks on Iraq's small Christian minority in recent years. Thousands of Iraqi Christians fled their homes in the northern Iraqi city of Mosul last year following a series of attacks.

In other news, the top U.S. military officer arrived in the northern city of Kirkuk Monday on a previously unannounced visit.

The chairman of the Joint Chiefs of Staff, Navy Admiral Michael Mullen, is meeting with Iraqi officials in the oil-rich city where ethnic and sectarian tensions are high.

Kurds want to make Kirkuk the capital of their largely autonomous region, but Arabs object.

In violence Monday, police in Mosul say an Iraqi soldier was killed when a bomb attached to a car exploded.

On Sunday, a bomb exploded in Iraq near a convoy of vehicles transporting U.S. Ambassador Christopher Hill. No one was injured in the attack.

Violence has declined in most of Iraq in recent months, but militants continue to stage attacks in northern Iraq and the capital, Baghdad.