A low-profile corporate approach and a reclusive founder with a military past have not stopped China’s Huawei Technologies from building an international telecoms equipment business, but they could make it a bit more difficult to buy a piece of US rival 3Com.

Huawei’s role in a proposed $2.2bn acquisition of networking company 3Com led by Bain Capital is drawing fire from critics in the US who fear it means Beijing will win undue influence over a supplier of security technology to the Pentagon.