An explosion and a huge plume of smoke near the Jeddah circuit have sparked new concerns in the Formula 1 paddock in Saudi Arabia.

Yemeni Houthi rebels said they again targeted a plant owned by the oil company Aramco in another rocket attack on Friday.

"We are waiting for more information from the authorities about what happened," said Formula 1 on Friday about the threatening scenes.

Shortly before the events, the racing series held its first training session ahead of the Red Sea Grand Prix scheduled for Sunday.

Just last Sunday, Houthi rebels launched attacks against Saudi Arabia using a missile and drones.

An Aramco plant in Jeddah was also hit, and fire broke out at an oil tank.

The scenes on Friday were reminiscent of these events.

Saudi Arabia is fighting the Houthi rebels in Yemen.

The war has triggered one of the greatest current humanitarian catastrophes.

Aramco is the main sponsor of Formula 1 and also an important sponsor of the British racing team Aston Martin, for which Sebastian Vettel drives.

The organizers of the race had said about the attack in the previous week: "This incident has no effect on the race weekend." The safety of everyone involved in the Grand Prix is ​​guaranteed, it said.

Saudi Arabia is considered to be quite safe compared to other countries in the region, but there have also been several terrorist attacks there.

At the end of 2020, the Islamic State terrorist militia claimed responsibility for an attack on a ceremony in Jeddah, in which two people were injured.

Strict safety regulations usually apply to major events such as sporting events in the country.

Despite the missile impact near the racetrack, Formula 1 has started the second practice session for the Grand Prix in Saudi Arabia.

With a 15-minute delay, the first cars rolled back onto the course on the Red Sea on Friday.

A meeting with all drivers and team bosses was called beforehand.

Later there should be "an official statement on how safety can be guaranteed," said Red Bull Motorsport Director Helmut Marko to the TV channel "Sky". Should safety be guaranteed for the remainder of the Grand Prix weekend can, "we should go," added the Austrian.

Saudi state television also confirmed a "hostile operation" by Houthi rebels near Jeddah.