A Russian official said a student attacked a vocational college Wednesday in Crimea, a rampage that killed 17 other students and left more than 40 people wounded, before killing himself.

The comments from Sergei Aksyonov, the regional leader in Crimea, were the latest in a series of shifting explanations by Russian officials as to what exactly happened at Kerch Polytechnic College in the Black Sea city of Kerch.

Russian officials at first reported a gas explosion, then said an explosive device ripped through the college canteen in a suspected terrorist attack. But witnesses reported that at least some victims were killed in an attack by a gunman or gunmen.

Aksyonov said on television that the student, a local man acting alone, killed himself after the attack.

Russia’s Investigative Committee, the nation’s top investigative agency, identified the attacker as Vladislav Roslyakov, 18. It said he was caught on security cameras entering the college with a rifle and firing at students.

The committee said all the victims died of gunshot wounds, contrasting with the previous statements by other officials saying they were injured in an explosion.

Reflecting the official confusion, Russian President Vladimir Putin said the victims were killed by an explosion just as the Investigative Committee was announcing they were fatally shot.

Putin deplored the attack as a “tragic event” and offered condolences to the victims’ families at a news conference in Sochi, where he had talks with Egyptian President Abdel-Fattah el-Sissi.

After the attack, local officials declared a state of emergency on the Black Sea peninsula that they had annexed from Ukraine in 2014. They also beefed up security at a new 19-kilometer (11.8-mile) bridge that links the peninsula with Russia that opened earlier this year.

Military units were deployed around the college.

The Investigative Committee initially said an explosive device that went off at the college’s canteen was rigged with shrapnel.

Sergei Melikov, a deputy chief of the Russian National Guard, said the device was homemade. Explosives experts inspected the college building for other possible bombs, according to Anti-Terrorism Committee spokesman Andrei Przhezdomsky.

Witnesses did not speak of an explosion but said one or more armed men attacked the school.

The Komsomolskaya Pravda newspaper quoted student Semyon Gavrilov as saying he fell asleep during a lecture and woke up to the sound of shooting. He said he looked out and saw a young man with a rifle shooting at people.

“I locked the door, hoping he wouldn’t hear me,” the paper quoted Gavrilov as saying.

He said police arrived about 10 minutes later to evacuate people from the college and he saw dead bodies on the floor and charred walls.

Another student, Yuri Kerpek, told the state RIA Novosti news agency that the shooting went on for about 15 minutes.

Olga Grebennikova, director of the vocational college, told KerchNet TV that men armed with automatic rifles burst into the college and “killed everyone they saw.” Grebennikova, who said she had left the grounds shortly before the attack occurred, said students and staff were among victims.

Russian Health Minister Veronika Skvortsova headed to the area to help coordinate assistance to the wounded and helicopters carrying emergency medical teams flew to the area.

Russia’s annexation of Crimea from Ukraine triggered Western sanctions. Russia has also supported separatists fighting the Ukrainian government in eastern Ukraine, a conflict that has left at least 10,000 people dead since 2014.

Over the past few years, Russian security agencies have arrested several Ukrainians accused of plotting terror attacks in Crimea, but no attacks have occurred.

(AP)