Italy's Alessandro Petacchi took his fourth stage win of this year's Giro d'Italia on Thursday.

Danilo Di Luca retained the overall lead, finishing the 203-km 18th stage in the same time.

Di Luca was among four Giro riders, given surprise drug tests late on Wednesday as part of a probe by the Italian Olympic Committee (CONI) into an investigation launched by Italian police in 2004.

In the final 550 meters, Petacchi found a way through and sprinted all the way to the finish line.

Argentina's Ariel Richeze tried to pass him but the Milram rider held him off for the 126th victory of his 12-year professional career.

Denmark's Matti Breschel finished third, a few metres behind.

Petacchi almost retired from the Giro after winning the 11th stage last Wednesday but said he now wanted to finish the three-week race in Milan on Sunday.

Friday's 179-km 19th stage is from Treviso to Terme di Comano near Lake Garda.

Source: Xinhua