The rebel Liberation Tigers of Tamil Eelam (LTTE) fired artillery at army positions in Mankerni in the district of Batticaloa on Saturday killing five soldiers in two attacks, the defence ministry said in a statement.
"Four soldiers were reported killed and two injured soldiers were admitted to hospital," the ministry said, adding another soldier was killed and one more wounded in the second attack in the same area.
The rebels said five civilians were injured on Sunday in the military artillery attacks.
Police said six civilians were also found shot dead in five places in the island's northern and eastern regions as well as elsewhere Sunday.
Investigations were underway to identify the victims and track down the killers, police said.
The killings came as Sri Lankan police commandos captured three more Tamil Tiger rebel bases in the island's east, raising to 11 the number seized from the guerrillas, an official said Sunday.
The elite Special Task Force commandos took control