Proton rocket launch
© Still from Roskosmos video
The launch of Russian Proton-M rocket went bad when its telemetry stopped, sources told media. There is concern that the rocket and its payload, a Mexican communication satellite, may be lost.

Telemetry stopped a minute before the MexSat-1 satellite was due to be placed into orbit. Roscosmos agency specialists are working to determine what exactly happened.

"It's not known yet what happened, but apparently the detachment of the third stage of the vehicle did not go as scheduled," a source in the space agency told RIA Novosti.

Another source said the third stage's engines shut down after Proton had spent 498 seconds in flight.

"Preliminary data indicate that the third stage and the Mexican satellite may fall in the Chita region [of Russia]. The emergencies ministry has been notified," the source told Interfax.

Local authorities said there were no reports in the Chita region of rocket debris falling anywhere near towns.

"If there were any casualties or damage, we would have known by now," a spokesman for the local branch of the emergencies ministry told RIA Novosti.

MexSat-1, a 5.4 ton communication satellite was built for the Mexican government by Boeing Satellite Systems.

Saturday's launch was initially scheduled for April 29 but was postponed at Boeing's request, as the company required additional time for satellite testing. Proton's previous launch was on March 29, when the rocket placed a Russian communication satellite into orbit.