The Afghan Taliban has announced the start of its warm-weather fighting season, an annual declaration marking the launch of a violent summer.
In an e-mail to media organizations on April 12, the militants said the so-called "spring offensive" had begun at 5 a.m. local time.
The Taliban said it was dubbing the campaign "Operation Omari" in honor of Taliban founder Mullah Mohammad Omar, who died three years ago.
The statement said waging jihad against the U.S. invaders was a holy obligation. The war is in its 15th year.
Hours before the Taliban announced their offensive, the U.S. Embassy in Kabul issued an emergency warning to U.S. citizens, saying it had received reports that insurgents were planning attacks on a major hotel in Kabul.
New Taliban leader Mullah Akhtar Mansur has escalated the war, spreading it to every corner of the country and even taking control of a major northern city, Kunduz, for a few days last year.
On April 11, a Taliban suicide bomber on a motorcycle killed at least 12 army recruits on a bus in eastern Afghanistan, hours after a similar attack killed two people in the capital, Kabul.