The Ministry of Finance received a third letter containing three bullets on Tuesday.

French Finance Minister Bruno Le Maire has received three letters containing death threats, including one this week with bullets enclosed, one of his aides said on Wednesday.

It was not immediately clear who sent the threats or what their motive was, but the letters had coincided with an increase in violence towards politicians, the aide added.

Anti-government "Yellow Vest" demonstrations unleashed some of the worst rioting in Paris in decades in late 2018 and the first half of this year. Protesters have also vandalised the offices of some ruling-party lawmakers.

"We accept democratic debate, that people might disagree with out policies, but this goes too far," the aide said.

He said the first letter was sent to police in the Basque country city of Bayonne in August, threatening to "pulverise" Le Maire's summer holiday house during the Aug. 24-27 G7 summit, hosted by France's president in nearby Biarritz.

The second was sent direct to Le Maire's residence in Saint-Pee-sur-Nivelle, this time threatening to target the minister himself.

The Ministry of Finance received a third letter containing three bullets on Tuesday. The sender said two of the bullets were meant for Le Maire and the third for his budget minister, Gerald Darmanin.

"This time they're 9mm. But when the time comes, it will be 11.43," the letter said, referring to a larger caliber pistol bullet.

Asked if the ministers' security had been strengthened, the aide said each were shadowed by a security officer, in line with standard protocol in France.

The minister intended to file a complaint with the police, the aide added.