At least three Afghan refugees have been killed after clashes between Pakistani security forces and refugees in south-western Pakistan, police say.
The refugees are being forced to move
Both sides say the other started the violence in Pir Alizai camp after officials tried to demolish homes.
The camp, set up for Afghan refugees after the 1979 Soviet invasion, is to be closed down by next month.
Islamabad says the camps are used by militants and drug gangs. Many refugees say they want to stay in Pakistan.
The clashes come a day after violence - in which at least 70 shops and three houses were destroyed - at another Afghan refugee camp, Katchagarhai in North West Frontier Province (NWFP).
The Pakistani authorities also want to shut Katchagarhai.
There were differing accounts as to exactly what happened during Wednesday's clashes at Pir Alizai camp in the province of Balochistan.
"The police and paramilitary soldiers went there to supervise demolition of abandoned houses. All of a sudden a few people came out of the camp and started firing," police chief Naseebullah Ghilzai told the Reuters news agency.
But refugees at the Pir Alizai camp, which is close to the Afghan province of Kandahar, accused police of trying to demolish their homes without any reason.
The refugees say that when they resisted, police opened fire.
Correspondents say that about 36,000 people live in Pir Alizai - one of four large camps including Katchagarhai that the Pakistani government plans to close by September. Around 300,000 people live in the four camps.
The camp is inhabited by refugees who have fled decades of fighting in Afghanistan. Although the Pakistan government says that refugees in the four camps can re-locate to other camps in the country, correspondents say that in practise this will be impossible for them to do.
The government has in any case said that it wants all two million or more Afghan refugees out of the country within the next three years.
Pakistani President Pervez Musharraf has said the camps must close because they are used by Taleban militants and criminal gangs trafficking opium and heroin produced by Afghanistan's booming drug industry.
A UN report released earlier this month found that most of those still in Pakistan want to stay.
Correspondents say that the issue of returning refugees is highly contentious in Afghanistan.
The country's foreign minister and refugee affairs minister have both been sacked by parliament in the last week for failing to stop the deportation of more than 50,000 Afghan refugees from Iran.
The BBC's M Ilyas Khan in Islamabad says that news of the impending camp closures has caused unrest among the refugees, who have established businesses in Pakistan and say there is no security or civic facilities in Afghanistan.
Refugees at the Katchagarhai camp near Peshawar have now asked for time to think through a government decision to wind up their camp, officials say.
The government has told all refugees to vacate their homes and businesses in the camp area by 30 June.
Pakistan's chief commissioner of refugees, Abdur Rauf Khatak, held a meeting with refugee elders at Katchagarhai, and gave them 20 days to agree to "peaceful" repatriation, or face forced eviction.
The Iranians are also trying to eject Afghan refugees
"It is a hard thing to prepare more than 10,000 families to move out in one go," Haji Dost Mohammad, an elder of the camp, told the BBC.
Pakistani officials say the decision to repatriate the refugees to Afghanistan was taken after consultation with the Afghan government and the United Nations High Commissioner for Refugees (UNHCR).
There are some 119 refugee camps in NWFP and in Balochistan which the government intends to close one by one over a period of three years.