PARIS (Reuters) - Two human rights groups said on Tuesday they had filed a legal complaint in Paris against cement firm Lafarge, saying some of its work in Syria may have made it complicit in financing Islamic State and in war crimes.

A spokeswoman for Lafarge, which became part of the Swiss-based LafargeHolcim Group last year, said it was investigating the complaint and that it did not do business with organizations classified as terrorists.

The legal complaint, lodged by SHERPA and the European Center for Constitutional & Human Rights (ECCHR), said 11 former Syrian employees of Lafarge Cement Syria (LCS) were also party to it.

LCS owns a cement factory in Jalabiya in northern Syria, between the IS stronghold of Raqqa and the town of Manbij. The company repatriated its expatriate staff in 2012 due to fighting in the region, which came under IS control in 2013.

After that, Syrian employees kept it running.

"According to the information Sherpa and ECCHR collected, LCS would have entered into arrangements with ISIS (IS) in order to maintain production, by paying for passes issued by the jihadist organization and buying raw materials necessary for cement production such as oil and pozzolana in areas under ISIS's control," said a statement announcing the legal complaint.

In June, a report in Le Monde newspaper said the Jalabiya plant had paid taxes to Islamic State in 2013 and 2014.

The Lafarge spokeswoman would not comment further on the allegations, but said Lafarge had always prioritized the safety of its employees and partners in Syria.

The company's factory in Jalabiya played a key role in the region in terms of providing jobs and developing vital infrastructure, she added.

The civil war in Syria, which has been a key base for Islamic State militants, has devastated the country, caused a massive refugee crisis and fomented tensions among outside countries backing the government or the rebels fighting it.

(Reporting by Sudip Kar-Gupta and Gilles Guillaume; Editing by Andrew Callus and Tom Heneghan)