GENEVA, May 15 (Xinhua) -- UN High Commissioner for Human Rights Zeid Ra'ad al Hussein on Tuesday expressed concern about a possible upsurge in violence during the run-up to Burundi's constitutional referendum.

Zeid noted in a statement released here that tension was highlighted following a recent deadly attack on a village in Burundi that left 26 civilians dead.

"Everyone will suffer if Burundi explodes into violence during or after the referendum," the UN human rights chief said, referring to the vote that will take place on Thursday.

"I urge the government to live up to its responsibilities to provide the people of Burundi with peace, security and a fully functioning democracy where everyone's human rights are respected, and the rule of law is applied equally to all," he said.

Ten women and 11 children were among the victims of the attack by unidentified armed men on the village of Ruhamagara, in Cibitoke Province, some 60 kilometers northwest of Burundi's capital Bujumbura last Friday.

"There are very differing accounts of whom the attackers may have been, and what the motive was," said Zeid. "It may have been political -- designed to impact on the referendum -- or it may have been carried out for other reasons, including revenge."

"Burundi is awash with rumors, political negotiations are deadlocked, and tensions are rising sharply in the wake of this attack, with many dreading what may happen during and after Thursday's referendum," he said.