An anonymous reader shares a report: The battle in the red-hot co-working space business is heating up. WeWork, the No. 1 player in the sector, allegedly sent two spies to infiltrate rival Knotel -- to steal info and some customers, Knotel claimed. The spies showed up at seven Knotel properties in Manhattan last month in a "systematic attempt to pilfer Knotel's proprietary information and trade secrets," according to a cease-and-desist letter the smaller company sent to WeWork. The Post has obtained a copy of the letter. The corporate espionage rookies may have pulled off the caper except, in a totally random happening, a Knotel employee recognized one of them as a friend of a friend, according to sources close to Knotel. While the pair used fake names to gain entry, according to the letter, a call to the Knotel worker's pal got the spy's real name -- and a couple of social media inquiries turned up the fact that he worked for rival WeWork, sources said. The letter to WeWork asks for a reply by Oct. 13 -- but so far Knotel hasn't heard a peep from its rival, according to CEO Amol Sarva. While inside the Knotel offices, visited Sept. 12-14, the luckless spies posed "as the founders of a fast-growing startup" and said they needed space for their six-person company, according to the letter.