A spokesman for rebels in South Sudan says security officials have arrested and severely beaten members of the rebels' publicity team, days before the expected arrival of rebel leader Riek Machar.

William Ezekiel, spokesman for the rebels' advance team in Juba, called the arrests of the 16 individuals "irresponsible."

Machar, who is to become vice president in a unity government with President Salva Kiir, is scheduled to return to Juba, the capital, on April 18.

In a statement Monday, the U.S. State Department accused government troops of launching fresh attacks on rebels in the country's western Bahr el Ghazal state.

That statement also cited credible reports that the rebels recently attacked government forces and civilians in the area and condemned that violence as well.