A week after the bombing, on 4 April 1986, an anonymous caller had contacted Police Commissioner; Mick Miller, stating that they had footage of the offenders responsible just before the explosion, the caller then stated they wanted US$500,000 to placed be in a Swiss bank account. The caller contacted Miller's office on five separate occasions, each of the calls made were traced to a series of public phone boxes in and around the St. Kilda area. In an attempt to get the caller to make contact again, Commissioner Miller and Victoria's Premier, John Cain offered the caller's amount as a reward for information (not in US currency or placed in a Swiss bank account). The caller was later identified as 38-year-old industrial chemist, Vladimir Rhychta who was arrested while calling Commissioner Miller's office from another public phone box by a St. Kilda detective on 16 April 1986 and charged with hindering a police investigation after it was found that Rhychta's information was false. As a result, Rhychta was convicted and sentenced to two month imprisonment. During the search for the anonymous caller, the taskforce then received information from a female witness who stated that she saw a male suspect parking a Commodore identical to the bomb car in front of the Russell Street Police HQ at around 12:30 p.m. on the day of the bombing, the witness' description was enough to provide detectives with an identikit picture of the suspect, the identikit matched the description of career criminal, Claudio Crupi. Crupi was a career armed robber who had a hatred towards police and at the time, had a grudge against a detective in the Victoria Police Major Case Squad who worked at Russell Street. Prior to the bombing, Crupi had been charged with a burglary and was on bail. Crupi had left Melbourne shortly after bombing, in a raid on Crupi's home, taskforce detectives found a homemade device on Crupi's kitchen table, making him a prime suspect, He was later arrested in Sydney on 15 April 1986 and was brought back to Melbourne. Under police questioning, Crupi denied that he had any involvement in the bombing but admitted that the homemade device recovered in his home was a fake and was meant to be planted at a police station in Flemington. A major breakthrough in the investigation came from a police report filed three weeks prior to the bombing. On