Google (GOOG) may not be a wireless carrier yet, but it’s certainly inching closer to becoming a full-fledged ISP. Google on Monday announced that it had acquired Wi-Fi service provider ICOA for $400 million, thus giving the company a “national provider of wireless and wired broadband Internet networks in high-traffic public locations.” ICOA describes itself as a company that “provides design, installation, operation, maintenance and management of WI-FI hot-spot and hot-zone Internet access,” so this seems like a really big move for Google into the ISP market. The company has also started rolling out its high-speed Google Fiber network in Kansas City and may bring it to more markets in the future.

UPDATE: In one of the weirder twists in recent memory, the CEO of ICOA has just written to TechCrunch to disavow the press release that was sent out in his company’s name. In short, he wrote that his company has “never had any discussions with any potential acquirers” and that the press release that hit the web Monday was “absolutely false.” Google has also told TechCrunch that reports of it buying ICOA are false.