127 people killed in weeks of violence in Ukraine

Ivan Simonovic, the UN assistant secretary-general for human rights, made the statement while speaking to reporters outside the Security Council chamber, where he just briefed the 15-nation council at a closed-door meeting on the current situation in the eastern Ukraine following his trip to Ukraine on May 14-19.

"There are numerous cases of illegal detentions, of abductions, especially affecting journalists as well as members of the electoral commissions, which certainly will make the elections in the east of the country much more difficult," he said.

"Apart of the difficult security situation in the east of the country, conditions are worsened by common criminality and its rise," he said.

"In addition to that, the social and economic rights of the people are being affected," he said, citing a shortage of medicine and a danger of undermining social services in the region.

Simonovic also warned of a "wave of displaced persons" emerging in the eastern part of the former Soviet republic.

During his visit to Ukraine, Simonovic said that United Nations monitors had documented 112 cases of unlawful detention, with the condition and whereabouts of 49 people still unknown. "Such abuses clearly indicate the breakdown in law and order in this part of the country," he said at a press conference in Kiev, capital of Ukraine.

On Monday, Simoovicdoubts cast his doubt over the prospects of holding the presidential election in eastern Ukraine, where he said the situation there had deteriorated so much that the region could collapse.

A total of 18 candidates would compete for the country's top post, with former Prime Minister Yulia Tymoshenko and businessman Petro Poroshenko emerging as front runners.

The election was called after former President Viktor Yanukovych was forced out of office in February and fled to Russia soon afterwards.

Ukraine has deployed tens of thousands of police and volunteers to maintain public order ahead of Sunday's presidential election.

Around 55,700 police forces and 20,000 volunteers would be mobilized to guarantee security during the voting across Ukraine, reports said, adding extra security measures would be taken in the country's eastern Donesk and Lugansk regions, which had plunged into chaos following anti-government protests.