Construction and mining services contractor Thiess has bought Silcar, a telco infrastructure firm with contracts to roll out the national broadband network (NBN).

Silcar had previously been a 50-50 joint venture between Thiess and German technology giant Siemens.

But under a deal reached between the two parties, Thiess has taken full ownership of Silcar.

“This acquisition broadens our services offering to our valued Thiess and Silcar clients and positions Thiess as one of the leading services companies in Australia,” Thiess managing director Bruce Munro told the market on Monday.

Shares in Thiess’ parent company Leighton Holdings, a construction giant, fell by 13 cents to $16.35 at 1030 AEST.

Silcar has contracts to install NBN optical fibre cables in Queensland, NSW and the ACT.