VILNIUS: A private Cessna plane crashed off the coast of Latvia on Sunday evening, Sweden's rescue service said, after NATO scrambled jets to follow its erraticcourse.

The Austrian-registered Cessna 551 aircraft was flying fromJerez in southern Spain, from where it took off at 1256 GMTwithout a set destination, according to FlightRadar24 website.

It turned twice, at Paris and Cologne, before headingstraight out over the Baltic, passing near the Swedish island of Gotland. At 1737 GMT it was listed on the flight tracker asrapidly losing speed and altitude.

"We've learned that the plane has crashed (in the ocean)north-west of the town of Ventspils in Latvia," a spokesperson for Sweden's rescue service said. "It has disappeared from the radar."

German and Danish war planes had earlier been sent to inspect the aircraft as it passed through those countries' airspace, but were unable to make contact, Johan Wahlstrom of the Swedish Maritime Administration said.

"They could not see anyone in the cockpit," he said.

German newspaper Bild reported that a man, a woman and their two daughters were aboard, without sourcing the information.

A Lithuanian air force helicopter was dispatched to the crash site for search and rescue at neighbouring Latvia's request, a Lithuanian air force spokesperson said. Latvia said it had also sent ships to the scene.

"Our ships are on the way to the position where the plane crash happened", Liva Veita, spokesperson of Latvian Navy, toldReuters.

A Stena Line ferry travelling from Ventspils to Norvik in Sweden has also been redirected to the crash site, according to the MarineTraffic website. The website also shows a Swedish search and rescue helicopter and airplane at the site.

The Lithuanian air force spokesperson said earlier that NATO fighter aircraft from the NATO Baltic Air Police mission in Amari airfield in Estonia had taken off to follow the plane, without giving any more details.

The company listed as the aircraft’s owner in Austria’s aircraft register, Cologne-registered GG Rent, could not immediately be reached for comment.