ISTANBUL (Reuters) - A helicopter carrying an executive of the Turkish Eczabicasi group and four Russians, including the firm’s Russian operations chief, crashed in Istanbul on Friday, killing all seven people on board, the city’s mayor was quoted as saying.

The helicopter crashed onto a highway shortly after take-off from Istanbul’s main Ataturk airport. Early media reports suggested it had hit a television tower but the district governor told reporters he was unable to confirm this.

Bulent Eczacibasi, chairman of the company with interests in pharmaceuticals and home products, and the governor of Istanbul had initially said five of the seven on board had been killed.

“We have no information on the details, the cause of the crash will become evident after the evaluations,” Eczacibasi said in a statement.

Istanbul mayor Kadir Topbas was quoted by broadcaster NTV and other media as saying all five passengers and two crew had died.

The road where the helicopter crashed was largely deserted at the time of the crash and no-one on the ground was hurt.