file photo: A Mahan Air passenger plane takes off from Mehrabad Airport in Tehran, Iran. AP
Iran's second-largest airline, Mahan Air, said it had been hit by a cyber attack Sunday, the latest in several targeting the company.
"Mahan Air's computer system has suffered a new attack," the company said in a statement.
"It has already been the target on several occasions due to its important position in the country's aviation industry."
All of its flights were on schedule, the statement added, but the company's website was down.
"Our internet security team is thwarting the cyber attack," spokesman Amir-Hossein Zolanvari told state television.
Mahan Air is Iran's main private airline and the second biggest after the national carrier Iran Air.
It has been on the blacklist of Iranian companies targeted by US sanctions since 2011.
In addition to a domestic network, it also serves destinations in Europe and Asia.
Iran last month accused Israel and the US of a cyber attack on its petrol distribution system that caused havoc at fuel pumps nationwide.
Israel's internet infrastructure has meanwhile been hit by cyber attacks by the Black Shadow hacking group, including against the largest Israeli LGBTQ dating site and an insurance firm.
The hacking group has not acknowledged any link to Iran, but the attacks are widely seen as part of a years-long covert war between Israel and Iran including physical attacks on ships and offensive cyber moves online.