A powerful explosion hit a gas pipeline in northwest Russia early on Thursday but officials said it was not caused by terrorism and exports were unaffected.
The huge blast hit a trunk pipeline outside Russia's second city of St Petersburg just minutes after midnight, shaking buildings as far as 5 kilometers (3 miles) away from the epicenter and setting off a fierce fire.
Officials said there were no casualties, but the power of the blast was such that many locals jumped into cars and drove to safety, causing congestion on motorways.
Emergency officials said they believed the explosion had been caused by the dilapidated state of the 80-cm diameter high-pressure pipeline rather than an act of terrorism.
"I personally exclude a version that this was caused by an act of terror," Vladimir Kudryavtsev, head of the regional emergencies ministry department, told Reuters at the scene. "There is no visible damage typical of an act of terror. A section of the pipeline was cut off, as if by a knife. But there are no signs of external impact."
Russia's Vesti-24 state television broadcast video footage of the accident showing giant orange and red flames licking black skies. The fire raged for almost two hours.
This Reuters reporter saw scorched land and blinking beams of torches as investigators and emergency teams were combing the marshy area in a nearby forest charred by the fire. It was hard to breathe as the air was still thick with soot and smoke.
The blast was so strong it formed a crater up to 50 meters (yards) long and 4 metros deep, Kudryavtsev said. Half of St Petersburg's 5 million people could see the conflagration.
Foreign Consumers Safe
A senior official said consumers in Russia and abroad were not hit. "This is not an export gas pipeline but rather a junction between two gas distribution stations," Sergei Gustov, head of Gazprom's local subsidiary Peterburggaz, told Reuters, adding St Petersburg too would not be cut off from gas supplies.
"There is a reserve gas junction," he added.
The explosion happened at a point where the pipeline ran close to a power station on the northern outskirts of St Petersburg.
The station was under maintenance works on Wednesday, with most staff away. "Otherwise, the consequences would have been much more serious," said Vesti-24 television.
Emergency services officials said windows at the power station had been blown out by the force of the blast. The emergencies ministry's Kudryavtsev said a huge, mangled section of the
pipe had flown 30 metros (yards) after the blast.
"It (the blast) was so strong that everyone's car alarms went off," said one eyewitness, local official Valery Garkavy. "People immediately started running out of their houses."