ABUJA, Nigeria – Nigeria’s acting President Goodluck Jonathan placed security forces on alert around the north-central city of Jos on Sunday after renewed sectarian violence in the city claimed about 200 lives.

The victims, most of them Christians, died in attacks early Sunday in the village of Dogo na Hauwa, about 3 miles south of Jos, which has been at the center of deadly Christian-Muslim tension, according to Mark Lipdo, the spokesman for a Christian non-governmental organization.

Nation

AIDS virus can hide in bone marrow

The virus that causes AIDS can hide in the bone marrow, avoiding drugs and later awakening to cause illness, according to research that could point the way toward better treatments for the disease.

Dr. Kathleen Collins of the University of Michigan and her colleagues report in this week’s edition of the journal Nature Medicine that the HIV virus can infect long-lived bone marrow cells that eventually convert into blood cells.

The virus is dormant in the bone marrow cells, she said, but when those progenitor cells develop into blood cells, it can be reactivated and cause renewed infection. The virus kills the new blood cells and then moves on to infect other cells.

Gunman shot dead near Texas Walmart

A man walked into a Walmart in Texas carrying at least two guns before engaging in a shootout with police outside the store, authorities said. The man was killed and an off-duty officer in the store who had tried to stop him was injured.

The shootout in the east Texas city of Commerce began when police received a call of shots being fired from a car in nearby Greenville, about 50 miles northeast of Dallas, said Marty Cunningham, city of Commerce spokeswoman.

Commerce police intercepted the car just outside the city limits, where the man exchanged gunfire with officers, Cunningham said. He then drove to Walmart and entered the store “carrying a long gun and pistol,” the spokeswoman said.

Cunningham said an off-duty officer from another agency was in the store and saw the man leave. The officer tried to stop the gunman in front of the store, where the officer and Commerce police exchanged gunfire with the man.

World

Taliban clashes with militia kill 50

Fierce weekend fighting in the north of Afghanistan between Taliban forces and another militant Islamist group has left an estimated 50 people dead, and the clashes were continuing late Sunday, according to reports from the area.

Local news reports quoted government and security officials from Baghlan province saying fighting erupted Saturday between the Taliban and fighters of the Hezb-e-Islami, a guerrilla faction under the command of longtime militia leader Gulbuddin Hekmatyar.