A security officer at a Scottsdale bar was allegedly stabbed five times early Sunday morning. Officers arrested a suspect Tuesday but were unable to charge him. Officers say a group of people were kicked out of Martini Ranch, at 7295 E. Stetson Drive, after an altercation inside the bar. 26-year-old Ian MacDonald allegedly got into a physical fight with bar security employees and stabbed 27-year-old Tyrice Thompson five times in the back, hip and arm. When officers arrived, they say Thompson was in serious condition. Police interviewed patrons but no one admitted to seeing or being involved with the stabbing. No security officers or other bar employees could identify who stabbed Thompson. No knife was found in any patron's possession. Officers found and arrested MacDonald where he works on Tuesday afternoon. During the interviews, police say MacDonald admitted to fighting with the bouncers, but denied stabbing Thompson. He was released pending further investigation and police say charges will be determined and filed at a later date.