The Serious Fraud Office (SFO) is investigating suspected bribery and corruption at Thales Group, a multinational aerospace and defence electronics contractor.

The company, which is headquartered in Paris and has a UK subsidiary employing more than 7,000 staff, is known in defence circles for its varied businesses, which include making missiles and launchers, supplying sonar systems for the Royal Navy’s nuclear submarines and designing the Queen Elizabeth-class aircraft carriers.

Investigators from the SFO and its French equivalent, Parquet National Financier (PNF), have informed the company of their joint investigation, with each agency concentrating on their respective jurisdictions.

The economic crime agencies cooperated on an investigation into Airbus, which resulted in Europe’s largest aerospace multinational paying a record £3bn in penalties in 2020, after admitting it had paid huge bribes on an “endemic” basis to land contracts in 20 countries.

Nick Ephgrave, the SFO director, said: “Working collaboratively with our international partners is a crucial factor in the fight against international corruption and with this case I hope to reinforce the SFO and PNF’s longstanding relationship, built on mutual cooperation and shared success.

“We will together rigorously pursue every avenue in our investigation into these serious allegations.”

A spokesperson for Thales said: “Thales confirms that the SFO and the PNF have commenced an investigation in relation to four of its entities in France and the UK. Thales is cooperating with the PNF in France and the SFO in the UK. The group complies with all national and international regulations. As the investigation is ongoing, Thales will not comment further.”

The announcement of the Thales investigation follows a search of the company’s offices in France, Spain and the Netherlands in the summer by law enforcement officials.

Reuters reported that the three searches were connected to two separate corruption investigations. At the time, Thales said “it strictly complies with national and international regulations”.

In the UK, defence accounts for most of Thales’s business, and it has been reported as growing rapidly.

Missiles made by the company in Belfast have been supplied – via the Ministry of Defence (MoD) – to fighters in Ukraine to shoot down Russian jets, drones and helicopters, and to hit tank targets. Earlier this year, Thales said sales had doubled since just before Moscow’s invasion and were expected to double again in the next two years.

In February, the then defence secretary, Grant Shapps, awarded Thales a near-£2bn contract to use artificial intelligence and virtual reality to keep British warships and submarines at sea for longer.

It holds a string of other government contracts with the MoD and Home Office and designs satellite propulsion systems. In 2019, it bought Gemalto, which holds the contract to make post-Brexit blue passports, for €4.8bn (£4.1bn).

Thales shares are listed in Paris, where the company is valued at more than €31bn.