KABUL - Already forced to operate in one of the world's most hostile environments for journalists, Afghan television stations are now being openly targeted by Islamist insurgents in a widening insurgency that threatens cities across the country.

The Taliban's brief capture of the northern city of Kunduz last month, the first time in 14 years of fighting it had taken a provincial centre, underlined how far its military strength has grown since NATO forces ended combat operations last year. Amid reports of summary executions, kidnappings and other abuses, the Taliban also issued a grim warning to two Afghan television stations, Tolo News and 1 TV, designating them as "military objectives".

Both stations had reported allegations of rape by Taliban fighters during the fighting in Kunduz, incensing the militant Islamist movement, which accused them of spearheading a U.S.-sponsored propaganda campaign. It said reporters and offices of the channels would be considered "enemy personnel" and would be "eliminated".

Tolo News, Afghanistan's first 24-hour news channel, has been one of the most active reporting operations in the country for years, employing dozens of journalists, many in volatile provincial areas. "It's unprecedented, I've never seen this," said its director, Lotfullah Najafizada.

Part of Afghanistan's largest private broadcaster, the station has won a reputation for fast, credible reporting in a shifting media landscape that features scores of newspapers, broadcasters and online news sites. It insists it was scrupulous in reporting all sides of the Kunduz fighting, including allowing Taliban spokesmen a right of reply.

"For us, it was the biggest story of the past 14 years," Najafizada told Reuters in an interview at the group's heavily guarded headquarters in Kabul. "We dispatched our biggest team to the city. About 10 reporters were on the ground." Moreover, twenty Afghan would-be migrants bound for Europe were killed in Iran on Sunday when the mini-bus in which they were travelling collided with a truck, state television said. Ten other Afghans suffered injuries in the accident, which occurred between Tehran and the central city of Qom, about 125 kilometres (77 miles) southwest of the capital, the television report said.

The accident happened early in the evening. It comes as authorities in Iran report an influx of Afghans fleeing insecurity in their country, which borders the Islamic republic. The governor of Sistan-Baluchistan province, which borders Afghanistan and Pakistan, warned that Iran needed to prepare for a tide of would-be migrants.

"Unfortunately, because of threats and insecurity in several areas in Afghanistan, we are witnessing a growing flood of Afghan migrants," Ali Ossat Hashemi said, according to media reports. "All regions of the country must prepare for the arrival of a wave of Afghan migrants who come with all their families and are in a dire situation," he said. "We must take further steps" to deal with the influx, he said.