Colombian authorities fined the companies Telmex Colombia and Telmex Telecomunicaciones, part of Mexican magnate Carlos Slim's business empire, for failure to respond to users' concerns.

The industry and commerce regulator fined each company 1.18 billion pesos ($612,000), the maximum allowed under laws governing Colombia's telecommunications sector.

The companies were fined for "repeatedly and systematically violating provisions that regulate the reception, handling and resolutions of requests, complaints and claims, known as PQR's, presented by their users," the regulator said Thursday.

Telmex Colombia and Telmex Telecomunicaciones, which provide fixed-line phone and Internet services, did not comply with their legal obligation to "systematically" handle hundreds of user complaints and concerns, the probe found.

That conduct "harmed the rights of the users of their services," the regulator said in a statement, adding that a decision was made to impose the fine "to protect the rights of users and consumers of telecommunications services."

The fine is subject to appeal. EFE