(AP) KABUL, Afghanistan - Nearly two dozen Afghan civilians were wounded on Wednesday when two grenades exploded inside a mosque compound and a bicycle bomb blew up in a city market, officials said.
The violence came a day after bomb blasts around Afghanistan killed at least 50 people in the deadliest day for civilians this year, as Taliban insurgents and other militants ramp up violence across the country.
The Taliban summer offensive coincides with Afghan police and soldiers taking on more responsibility for security while international forces start to withdraw.
Separately, NATO reported that one of its service members was killed Wednesday in an insurgent attack in the east. NATO did not disclose the nationality of the soldier or provide any more details. So far this year, 285 international troops have been killed in Afghanistan.
At least nine worshippers were wounded when the grenades exploded during morning prayers at a mosque in Baghi Sara area, Khost police chief Sardar Mohammad Zazai said. One exploded inside the mosque and the other went off in a courtyard outside. The third failed to detonate.
Zazai blamed Taliban insurgents for the attack.
"This was the work of the enemy," he said. "It cannot be a private dispute. Why would anyone be so angry to throw grenades in a mosque while people are praying?"
He said many of the worshippers were Afghans who work at the nearby U.S. post, Forward Operating Base Salerno.
Taliban spokesman Zabiullah Mujahid issued a statement that did not acknowledge the mosque attack but claimed an insurgent suicide bomber had attacked a U.S. base in Khost, causing several American casualties.
A spokesman for the NATO military coalition said Wednesday that there was no attack on the Salerno base, which is close to the mosque in Baghi Sara. Lt. Col. Hagen Messer said the American personnel at the base reported hearing gunfire from the mosque but that Afghan police were investigating.
At least 14 people, including four women and a policeman, were injured when explosives set up on a bicycle exploded at a market in the city of Herat while people were shopping for an upcoming Muslim holiday, said Noor Khan Nekzad, a spokesman for the provincial police.
The latest violence follows a particularly bloody day for Afghanistan. Suicide bombers launched multiple attacks in remote Nimroz province in southwestern Afghanistan near the Iranian border on Tuesday, killing dozens of people, including shoppers buying sweets for a Muslim holiday. The bombings left charred and smoldering bits of cookies and dried fruit among the bodies on the ground.
A separate market bombing later Tuesday, this one in Kunduz in the north, killed 10 people, including five children.
And in the eastern province of Paktika, a car hit a roadside bomb. Four children died in the blast, provincial spokesman Mokhlis Afghan said, bringing Tuesday's death toll to 50 - 11 police and 39 civilians. At least 110 people were wounded in all the attacks.
The attacks came as the Taliban and their allies step up their assaults in a display of force that often results in civilian carnage. Militants are especially trying to weaken the still-developing Afghan security forces, who are to assume control across their homeland in 28 months, when most foreign combat troops will have left.
The Taliban "want to expand their influence - show that they are everywhere," said Afghan political analyst Jawid Kohistani. "They want to show that the Afghan police are not strong enough, so they are targeting the security forces and the government."
Gen. John Allen, the top commander of U.S. and NATO forces in Afghanistan, said Tuesday's attacks were "acts of intentional mass murder."
"By targeting innocent civilians in populated areas, the insurgents have again shown they will kill non-combatants without hesitation to advance their backward-looking plans for Afghanistan," Allen said in a statement. "Once again, I call on (Afghan Taliban leader) Mullah Omar to rein in his murderers. His intentions not to target civilians are hollow."
In past statements, Omar has asked his fighters to avoid civilian casualties. In one message in 2010, for instance, he said: "Pay attention to the life and property of the civilians so that ... your jihad activities will not become a cause for destruction of property and loss of life of people."
The U.N. reported last week that civilian deaths were lower in the first six months of 2012 than in the first half of 2011, but that an onslaught of summer attacks from insurgents were threatening to reverse that trend.
In all, 1,145 civilians were killed in Afghanistan between January and June of this year, according to the U.N. report.