Turkey said Saturday it was open to new bids in its plan to acquire its first long-range anti-missile system, should its controversial negotiations with China come to nothing.

"It is not a finalized deal yet. If U.S. and European companies make us better offers, we will continue to talk with them," said Foreign Minister Ahmet Davutoglu, who was quoted by Turkish newspapers.

The Russian parliament has approved a bill toughening sanctions in terrorism cases ahead of the Winter Olympic Games next February, including a controversial measure that makes families of terrorists financially accountable for the damage.

The bill makes it possible for officials to investigate the property of relatives of "a person who has committed a terrorist act" and make such people financially accountable for damage done by this person, according to parliament documents.

A Greenpeace activist Saturday staged a protest in a tent suspended from the second floor of the Eiffel Tower against Russia's detention of 30 members of the environmental lobby group.

The activist also unveiled a banner with the slogans "Free the Arctic 30" and "Militants in prison, climate in danger", forcing authorities to close the French monument to tourists in the morning.

Russia is investigating reports one of its citizens was kidnapped in Syria after a video of the man pleading to be rescued was posted online, a report said Thursday.

The video, posted on YouTube, shows a man who identifies himself as Russian citizen Sergei Gorbunov and asks Moscow to help free him.

Greenpeace on Thursday urged Russia to release its crew members after investigators reduced the charge against them from piracy to hooliganism over their protest on an Arctic oil platform.

"Our general position has not changed: the investigation must wind up this laughable case, apologize and set them all free," Greenpeace lawyer Anton Beneslavsky told Agence France Presse.

Russia said Wednesday it had reduced piracy charges against 30 Greenpeace activists detained at sea while protesting against Arctic drilling, to the lesser count of "hooliganism".

The Investigative Committee, the Russian agency in charge of probing serious crimes, said it had "taken the decision to reclassify the crime as hooliganism".

Turkish fighter jets intercepted a Russian military plane in international airspace over the Black Sea, the military said Wednesday, without giving a reason.

"Two F-16 jets were scrambled to prevent a potential violation of (Turkish airspace)" after the Ilyushin II-20 plane was detected flying in parallel to Turkish coast, the general staff said in a statement about Tuesday's incident.

NATO and Russia said Wednesday they had made no progress in settling sharp differences over a planned missile defense system for Europe but pledged to continue efforts to resolve the row.

"It is no secret that we have not yet found the way to work together on missile defense," NATO head Anders Fogh Rasmussen said after a meeting of the NATO-Russia council.

Russia said Wednesday it will boycott maritime court hearings sought by the Netherlands over the fate of 30 crew members of a Greenpeace ship who were detained during a protest against Arctic oil drilling.

"The Russian side has informed the Netherlands and the International Tribunal for the Law of the Sea... that it does not intend to take part in the tribunal's hearings," the state-run RIA Novosti news agency quoted an unnamed Russian foreign ministry official as saying.

Six servicemen were killed and two others wounded in an explosion at a military firing range in Russia, the defense ministry said on Tuesday.

"As a result of an explosion six air force servicemen died," the state RIA Novosti news agency quoted a defense ministry statement as saying.