* At least 35 unaccounted for after overnight blaze
* Six bodies found, no sign of survivors
* Governor says ward held severely ill patients
* Criticism of poor safety at state institutions may rise (Adds six bodies found, negligence case opened)
By Steve Gutterman
MOSCOW, Sept 13 (Reuters) - A fire raged through a Russian psychiatric hospital on Friday, killing at least six people and leaving dozens missing, the second such blaze this year and one likely to increase criticism of the state's treatment of the mentally ill.
Police were searching the area in the village of Luka north of Moscow for survivors of the pre-dawn fire at a ward for severely incapacitated patients, according to emergency and law enforcement officials.
Emergency authorities had recently sought to have the run-down wood, brick and concrete building condemned as unfit for use, a senior official said. In response to the fire, a federal criminal investigation into suspected lethal negligence began.
State television showed firefighters spraying water on the smoking, blackened ruins of the ward at the hospital - footage that has become sickeningly familiar after a number of deadly fires at state institutions in Russia in recent years.
An orderly died while trying to save patients at the hospital in Luka, which is in Novgorod province between Moscow and St Petersburg, the federal Investigative Committee said. It said 35 people were unaccounted for.
Six bodies had been found by mid-morning, the Emergency Situations Ministry said.
Some of the missing may have escaped the hospital, ministry official Oleg Voronov said on Ekho Moskvy radio, but none had been found hours after the blaze, which broke out before 3 a.m. (2300 GMT on Thursday), by police combing the area.
The fire left little but the concrete foundation of the single-story building housing male patients at the hospital. Voronov said there were about 60 people in the building, most of them patients, when the blaze broke out.
Officials said more than 20 patients were evacuated.
Investigators and the chief doctor at the hospital said they suspected a patient started the fire, Russian news agencies reported, but regional governor Sergei Mitin said it might have been accidental.
"Medical personnel saw a patient who was shrouded in flames. ... It's possible that he was smoking in bed and the mattress caught fire," Mitin said, according to Interfax. He said the ward that caught fire housed severely ill patients.
Critics of the government say state authorities frequently blame the victims of fires in order to avoid culpability.
Emergency officials and prosecutors had sought to have the building condemned as unsafe, but a court instead ordered management to correct unspecified flaws by August 2014, the head of safety oversight for the Emergencies Ministry said.
"The building that burned was unfit for use," the official, Yuri Deshevykh, told state-run Itar-Tass news agency.
There have been many fires with high death tolls at state institutions such as hospitals, schools, drug treatment centres and homes for the disabled in the past decade, raising questions about safety measures, conditions and emergency exit routes.
In April, a fire at a psychiatric hospital outside Moscow killed 38 people.
The death rate from fires is much higher in Russia than in Western countries including he United States.
The nation of 142 million is also plagued by accidents on its roads, rails, rivers and in the workplace, taking the shine off a post-Soviet recovery for which President Vladimir Putin - in power since 2000 - claims a measure of credit.
Critics say Putin's top-down ruling style fosters a culture of negligence and that he has made little progress stemming the corruption and corner-cutting that is blamed for many deadly accidents.
Yuri Savenko, president of the independent psychiatric association of Russia, said the dilapidated state of psychiatric hospitals was pushing up death tolls from fires. He said a third of the buildings at such facilities had been declared unfit for use since 2000. (Editing by Mark Heinrich)