A Grand Theft Auto 5 PC modder has claimed publisher Take-Two Interactive used private investigators to discourage him from continuing work on FiveM, an alternative GTA 5 online mode where players could use mods without being banned.

Posting on Reddit, the modder--using the alias ntauthy--said two private investigators came to his home and claimed to have been sent by Take-Two, parent company of GTA 5 developer Rockstar Games.

"So I just got a pair of PIs at my door claiming to be sent by Take-Two, handing me a phone with a person somewhere in the UK or US or whatever to 'discuss how to cease activities with regard to Grand Theft Auto,' [and] that 'they know what happened before with Activision and want to not get the lawyers involved this time,'" he said.

"However, they 'have tested their legal standing already and are quite certain of their point' and 'aren't willing to accept any solution other than ceasing my activities,'" he explained further.

Ntauthy added the Take-Two representatives he claims to have spoken to wouldn't disclose details on any conversations the company is having with other mod developers and "didn't want to talk about general modification policy as 'it was just about my case.'"

Ntauthy did not say what his response was, his plans regarding the development of the mod, or further actions Take-Two may have indicated it will take. At the time of going to press, the accuracy of his story cannot be independently verified.

A group of modders attached to the development of FiveM were previously banned from the game in August 2015. Although it claimed to offer an "advanced multiplayer environment for people to play on dedicated servers with user-made game modes," Rockstar said it believed the project was designed to facilitate piracy.

"The FiveM project is an unauthorised alternate multiplayer service that contains code designed to facilitate piracy," a Rockstar representative said in a statement.

"Our policy on such violations of our terms of service are clear, and the individuals involved in its creation have had their Social Club accounts suspended."

GTA: Multiplayer, a separate mod project aimed at offering an alternative online mode, issued a statement saying it would cease development and shut down, something that was "not an easy decision to make" as it had "worked more than two years on" it.

"[Take-Two] have contacted us and they asked us to stop GTA: Multiplayer, because from Take-Two’s point of view GTA:MP is a rival of their business," it said.

"We, as developers, respect other developer’s intellectual property and their legitimate interests. Rockstar’s developers have invested so much time to create this beautiful game. We have repeatedly stated our position: We are not going to cross this line, we won’t damage them."

It continued: "We clearly see that this may not only result in problems for us, the mod creators, it even may result in a Social Club ban for you, and this is something we do not want to be responsible for. We always respected the copyright of others, and we will not stop doing so."

The creators of GTA: Multiplayer claim to have been in contact with Rockstar and "got feedback" from the studio, but noted that its approval didn't necessarily reflect the attitude of its parent company Take-Two.

From the statement, it seems the issue of potentially enabling piracy was a core factor in the cease and desist request.

"We have never endorsed piracy," the GTA Multiplayer statement continued, "in fact we encouraged the buying of the game and never touched Rockstar Social Club as other modifications did or still do."

GameSpot has contacted Rockstar Games and Take-Two for comment.

In November 2015, Take-Two Interactive said microtransaction sales from GTA Online showed "strong growth" since launch and the mode had reached 8 million players per week.