By Richard Balmforth
KIEV (Reuters) - Ukraine approved sweeping laws on Tuesday to stamp out corruption and curb Soviet-era state surveillance of political life ahead of a parliamentary election its pro-Western leaders hope will push the country towards the European mainstream.
But violent clashes between police and protesters in the first real anti-government demonstration in Kiev since the "Euromaidan" upheaval last winter highlighted the potential for disorder in the run-up to the election on Oct. 26.
President Petro Poroshenko, elected in May after his predecessor, the Moscow-backed Viktor Yanukovich, was ousted, wants a calm run-up to a poll he hopes will endorse his efforts to end a separatist conflict in the east and build closer economic and political ties with the European Union.
The demonstrators, many of them masked, threw smoke-bombs and used air guns to shoot out windows of the parliament building, forcing an early end to the session, which also voted in a new defence minister.
Their motives and party affiliations were not clear, though they appeared to be fringe nationalists. However, members of two nationalist parties who were nearby denied any links to the violence.
The laws backed by parliament are aimed at cleaning up Ukraine's profile and heading off suspicions among critics, including in the EU, that Kiev is dragging its feet on reforms.
The new legislation, which tackles high-level graft and reforms the prosecutor general's office, has been sought by the EU, which has signed an association agreement on closer trade and political ties with the former Soviet republic.
"The offshore era has ended," Prime Minister Arseny Yatseniuk said, referring to laws under which government, judiciary and law enforcement officials will have to declare their own and their families' assets and financial transactions.
"UNDER THE MICROSCOPE"
The declared income of civil servants will be measured against lifestyle and property holdings. Officials' bank accounts will be open to monitoring by a state committee.
Reform of the prosecutor's office will curb the functions of a Soviet-era institution that has long been used by authorities in Ukraine as a tool to harass the political opposition.
Bribery has been widespread at virtually all levels of Ukrainian government and public life since independence from the Soviet Union in 1991. International watchdogs say it worsened in the past four years under the ousted Yanukovich.
"Now every civil servant will be under the microscope. Those who illegally hold something will be brought to justice," Yatseniuk said.
Echoing those comments, Poroshenko said after the vote: "We have taken a decisive step in the struggle with corruption, a cancerous tumour which eats away at our society."
The reform of the prosecutor's office relieved it of rights given to it by Soviet dictator Josef Stalin, he said.
In other legislation rushed through during the last session of the current parliament, National Guard chief Stepan Poltorak became new defence minister. He replaces Valery Heteley, who has faced criticism over the rout of Ukrainian forces in the east.
The battlefield losses at Ilovaisk, east of the rebel-controlled eastern city of Donetsk at the end of August, inflicted by what Kiev said was a direct intervention of Russian troops, forced Poroshenko to abandon attempts to crush the separatists and he agreed to a ceasefire from Sept. 5.
The ceasefire forms the core of his peace plan that would also grant provisional self-rule to the separatists.
But it is increasingly under pressure. A military spokesman said on Tuesday that seven more Ukrainian servicemen had been killed in the past 24 hours - six of them in two landmine explosions - bringing to about 50 the number of Ukrainian military personnel killed since the ceasefire came into force.
In the south-east, authorities in the coastal town of Mariupol said seven people had been killed and at least 15 others injured on Tuesday when shells struck a group of people gathered for a funeral in the nearby village of Sartan.
Opinion polls suggest Poroshenko's political bloc will perform well in this month's election, bringing him the coalition of parliamentary support he is hoping for.
But he faces internal opposition from parties who fear he may make too many concessions to the separatists in the heavily industrialised, mainly Russian-speaking east, who are pressing for unity with Russia.
The United Nations says more than 3,600 people - Ukrainian troops, separatists and civilians - have been killed in eastern Ukraine since the fighting erupted there in April.
(Additional reporting by Natalia Zinets and Pavel Polityuk; Editing by Gareth Jones)