Oct 8 - Lufthansa Group (LHAG.DE) and three Indian airlines will suspend flights to Riyadh, they said on Thursday, as Yemen's Iran-aligned Houthis renewed threats against airlines after claiming an attack on the Saudi capital's airport.

A Lufthansa spokesperson told Reuters the German group's airlines would suspend flights to Riyadh through October 16 due to "current developments in the Middle East".

India's largest airline IndiGo (INGL.NS) said it had cancelled all flights to and from Riyadh until October 9.

Air India and Akasa Air also told Reuters they had cancelled all flights to and from the Saudi capital until October 10.

Air India added that a flight from Delhi to Riyadh returned to the Indian capital on Thursday, while Akasa Air cancelled two scheduled services.

Smoke was seen rising from a stationary aircraft at Riyadh airport earlier on Thursday, according to a witness and three people briefed on the matter.

Yemen's Iran-aligned Houthis said they had struck King Khalid International Airport in Riyadh with a ballistic missile, although there was no immediate confirmation from Saudi authorities.

Saudi authorities said on Wednesday that three people had been killed this week in strikes on Riyadh airport and Abha airport in the southwest.

Several dozen international flights bound for Riyadh on Thursday evening have been cancelled, data from global flight tracker FlightRadar24 showed.

Data compiled by aviation analytics firm Adds IndiGo and Akasa Air cancellations, additional details in paragraphs 2 to 7