A Moscow Public Prosecutor said Friday he believes that an American exchange student found dead last week was murdered and that his office has launched a homicide investigation.


Original police reports on the death of Anthony Riccio, 21, on Sept. 20 said he committed suicide.


Alexander Shlykov, Public Prosecutor for Moscow's Chertanovsky area in southern Moscow and investigator of the case, said he had ruled out the possibility of suicide and now believed Riccio's death was murder.


"Recent investigations give us evidence to think that this was a murder," he said, adding, "Personally, I think that this was a murder and not suicide."


Toxicology test results completed Thursday showed no trace of alcohol or narcotics in Riccio's blood, Shlykov said. The results, along with new evidence from "our recent works with witnesses and other checks," had convinced him that there was no motive for suicide.


No arrests have been made and police have no suspects, Shlykov said. He declined to give further details on the investigation.


Riccio, a student from Brown University in Providence, Rhode Island, was found on the pavement after having apparently fallen from the 16-floor dormitory building.


Police officials gave conflicting reports after his body was found, with some saying there was a rope around Riccio's neck, leading to the assumption of suicide.


However, other reports, including that of a student who identified the body and covered it with a sheet, said no rope was found.


Family and friends have denied the possibility of suicide.


John Riccio, the student's father, said in Glastonbury, Connecticut that he had little time for news of the investigation to sink in.


"We still don't get our son back," he told The Moscow Times. "We are comfortable with the fact that it wasn't just brushed away."


The dorm where Riccio lived is in an industrial area of southern Moscow. Since his death, four other American exchange students in the same program have moved out to another dorm in central Moscow.


In recent years, Russian and foreign students have complained about lack of security in their dormitories.


Riccio had only been in Russia for 10 days and had just begun a year's study at the Moscow State Humanities University under the auspices of a program sponsored by the American Collegiate Consortium.


The Russian coroner's preliminary report produced within days of Riccio's death determined the cause of death as "mechanical asphyxiation" and underlined the word "murder."


After the body was returned to the United States, American pathologists drew the same conclusions as the Russian coroner, that the cause of death was asphyxiation caused by external pressure on the neck, according to Theresa Braine, a reporter on The Hartford Courant newspaper in Connecticut.


Thomas Pickering, the U.S. ambassador in Moscow, raised the issue with Russian Foreign Minister Andrei Kozyrev, who assured him the investigation would be thorough and complete, The Courant reported Tuesday.


Riccio's body was returned to the United States last Saturday. About 1,000 mourners attended a wake on Tuesday in Glastonbury, Braine said.