Pirelli's tyre test in Bahrain has been marred by a tyre blow-out, according to a tweet from Mercedes driver Nico Rosberg.
The Italian company are to continue as Formula One's tyre supplier during the 2014 season and Red Bull, Ferrari, Mercedes and Toro Rosso have all taken part in a three-day test at the Sakhir circuit to test the new rubber.
Nico Rosberg tweeted from Sakhir he'd spun at 320km/h
Pirelli found themselves under the spotlight when a spate of tyre failures blighted the British Grand Prix at Silverstone which led to a change in tyre construction for the second half of the season.
Rosberg's Mercedes team-mate Lewis Hamilton was among the drivers to be affected on that day, and the German revealed on Twitter that he himself had suffered a frightening blow-out on Thursday morning.
The tweet, which was later deleted, read: "Just spun at full speed 320km/h on Bahrain straight cause my tyre blew up without warning. Thanks to that need to get some toilet paper now..."
"Incidents can happen," a Pirelli spokesperson told Autosport. "This is what testing is for."