Indian mobile phone company Vodafone Essar has warned a customer that it will sue him for defamation over comments he made on his Facebook page about the firm's services, a spokesman said on Wednesday.
"There has been a legal notice that has been issued," the spokesman told AFP, without elaborating.
India's third-largest cell phone operator by subscribers sent the notice to Dhaval Valia on May 26, asking him to stop making defamatory statements on the popular social networking site and remove earlier posts within 48 hours.
Failure to do so would lead to civil and criminal proceedings against him, according to the notice, which has been seen by AFP.
The business journalist was also warned about sending "unnecessary, unneeded and unwarranted" text messages to senior managers and about posting the phone numbers of Vodafone customer care officials for other people to complain.
The text messages had caused the staff "mental trauma", while the statements were "an attempt to defame the name and spoil the goodwill of our client (Vodafone) in the market," the notice from legal firm India Law Alliance said.
The dispute centres around the availability of third-generation mobile services in the northern Mumbai suburb where Valia lives.
Valia is now pressing a counter claim against Vodafone for "mental harassment, twisting facts, and arm-twisting consumers into submitting to their faulty and misleading ways and thus acting against the rights of consumers."
He also accused Vodafone of breaching privacy laws by accessing his Facebook account, denied "malicious" conduct and said he has emails from Vodafone executives in which they admit "hiccups" with the 3G roll-out.
Valia told AFP that he had complained to India's advertising standards watchdog and claimed the firm was trying to silence him.
The Vodafone spokesman said they would not be commenting on Valia's specific claims.