BRUSSELS (Reuters) – The European Commission launched an investigation on Thursday into imports of optical fibre cable from China, which EU manufacturers believe are being sold in Europe at artificially low prices.

The case comes as the 27-member European Union wants the digital economy to be a key part of its economic recovery and demands a greater opening of Chinese markets.

Europacable, which brought the complaint on behalf of the EU producers, said some 1.2 million kilometres (745,000 miles) were installed in Europe last year, with 15-20% coming from China. Chinese imports rose by 150% from 2016 to 2019, the industry group said.

EU anti-dumping investigations take up to 15 months, but provisional duties can be put in place within eight. Final tariffs, if imposed, would normally apply for five years.

The largest producers in the EU are Italy’s Prysmian Group PRY.MI, U.S. company Corning GLW.N and France-based Nexans NEXS.PA and Acome.

Major Chinese optical fibre cable makers include Yangtze Optical FC 6869.HK, Hengtong Group 600487.SS, Fiberhome 600498.SS and Futong.

The Commission has already carried out a series of investigations into glass fibre products from China and imposed tariffs. It also has 29 ongoing trade defence investigations, 18 of them including products from China.