MONZA, Italy -- Tomas Enge, who a year ago became the Czech Republic's first Formula One driver, tested positive for cannabis after a Formula 3000 race in August, his manager Antonin Charouz has said.

The governing International Automobile Federation (FIA) said Thursday that the 26-year-old had returned a positive drug test at the Hungarian round of championship but did not name the drug.

"The substance in question is cannabis, either from marijuana or hashish," Charouz said on Czech state television.

In the local daily Mlada Fronta Dnes, Enge refused to comment on the situation.

The paper, quoting Jaroslav Nekola, head of the antidoping committee, said Enge was found to have 10 times more than the acceptable limit of THC (tetrahydrocannabinol, or cannabis) in his body.

Charouz said he did not believe Enge had willingly taken drugs.

"Tomas could have breathed it in at a disco. Someone could have slipped him it, baked it into something he ate or drank," Charouz said.

FIA sources said Enge was believed to be the first driver to fail such a test in an international championship organised by the governing body.

Enge, who drove three times for the now defunct Prost Formula One team at the end of last season, provided a urine sample after the F3000 race at the Hungaroring on August 17 after being randomly selected.

The team was notified this week about the result by the FIA, a year after Enge made his F1 debut with Prost at the Italian Grand Prix. A second sample is still being tested.

"I knew about the positive test at the beginning of the week," Enge told the newspaper.

Doping offences are taken extremely seriously in motorsports, particularly if recreational drugs are involved, because impaired judgement and dulled reactions can prove fatal in close-quarters racing.

Thursday's announcement came only days before the final round of the F3000 season at Monza in Italy at which Enge could be crowned champion. Enge lies second in the F3000 championship, a support series at most Formula One grands prix, after four wins this year.

After leading for much of the season, he is now a point adrift of France's Sebastien Bourdais who has 55, with Italy's Giorgio Pantano also on 54 but with fewer wins.

The FIA said the results would be provisional until a hearing of its World Motor Sport Council on Oct. 1.