Roadside bomb kills 19 civilians in south Afghanistan
At least 19 Afghan civilians have been killed by a roadside bomb in southern Helmand province, said officials.
The incident occurred in the province's volatile Sangin district - a Taliban stronghold - Helmand spokesman Daud Ahmadi said.
The dead are said to include women and children, many from the same family.
The deaths come amid mourning for 59 people, mainly Shia worshippers, who were killed in twin bomb attacks in the country on Tuesday.
President Hamid Karzai on Wednesday cut short a trip to Europe to return to Kabul, where he will visit people wounded or bereaved in the worst incident - the suicide bombing of a Shia shrine on the holiest day of the Shia calendar, which killed 55.
Coupled with a smaller bombing in the northern city of Mazar-i-Sharif, the attacks have raised fears that the violence in Afghanistan may be taking on a new sectarian character.
An investigation is under way, security officials confirm.
"Nineteen people including seven women and five children have been killed" in Wednesday's attack, Helmand province security force commander Mohammad Ismail told Reuters news agency.
"The seven women are from the same family. Five people have been injured," he added.
The injured were being treated at a Nato base, another report said.
There was no immediate claim of responsibility for the attack, but this is a common occurrence with roadside bombs, which are usually blamed on Taliban-led insurgents.
According to the UN, 1,462 Afghan civilians were killed in the first six months of 2011, a 15% jump over the same period in 2010.
Many bereaved relatives in Kabul and Mazar-i-Sharif were burying their dead from Tuesday's bombings in emotional scenes on Wednesday.
In western Kabul, a group of mourners carried four bodies in a procession through the city's main Shia cemetery, AP news agency reported.
"They are martyrs! We honour them!" they shouted.
One US citizen was among those killed from the Kabul bombing, the US embassy confirmed - saying the victim was not a government employee but refusing to divulge further details.
One of those mourning told AP said no place felt safe any more.
"Killing Muslims in front of a holy shrine, it is unbelievable," said Mohammad Nahim, 35.
"Last night I told my children not to visit any shrines after dark. It is too dangerous."
He said graphic images of mounds of bodies had been shown on television as his family was eating dinner the night before and they all started crying.
"The man who owned the shop on my street corner, the man I bought vegetables from, he was killed in the attack," Mr Nahim said.
As well as visiting the wounded and bereaved, President Karzai would hold an emergency meeting with security chiefs on the violence, reports said.
On Tuesday, he said it was the first time such an attack had taken place on such an important religious date in the calendar.
Observers say the attack has raised fears of a new phase of sectarian conflict similar to those in Pakistan or Iraq.
The Taliban have denied any role in the attack, and some Afghan officials are pointing the finger at Pakistan-based militant groups.