Japanese police have finally arrested a long-sought after thief who dressed as a ninja during burglaries. He is 74.

Authorities say they were surprised to learn the age of the thief, who was apprehended after he didn’t cover his face when security camera was present and was later caught in July, according to the BBC.

Police now think that he is the infamous “Ninja of Heisei,” who is thought to have committed more than 250 burglaries over the course of eight years, the BBC reports.

Investigators had failed to solve the mysterious case surrounding the series of break-ins that were carried out by a suspect in all-black. They had always assumed that whoever it was, they would be much younger, according to the BBC.

After putting the thief on surveillance following his initial slip up in front of the security camera, police were able to track the suspect during the day. His behavior seemed different from a typical elderly man, according to the outlet, but he did not commit any crimes.

Investigators said that he proceeded to enter an abandoned building and changed clothes, waiting until dark before emerging to steal.

“He was dressed all in black just like a ninja,” a senior official in Osaka said, according to the BBC.

Investigators said that the thief was able to run “on top of the walls” with ease rather than in the streets, the BBC reported.

Following his arrest, the thief was quoted as saying: “If I were younger, I wouldn’t have been caught. I’ll quit now as I’m 74 and old enough.”

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