Courtesy HAZ / Michael Thomas

A ransom note signed by the "Cookie Monster" was sent to a German newspaper, along with a photograph of somebody dressed up as the "Sesame Street" character.

MAINZ, Germany — When a famous 44-pound metal cookie was stolen from outside a German factory, there was one obvious suspect. But few would have expected the Cookie Monster himself to claim responsibility for the crime.

The giant golden snack has been a landmark as part of a statue at leading cookie manufacturer Bahlsen's site in Hannover since 1913 until it vanished on Jan. 21.

This week, the first clue emerged when a ransom note made up of letters cut from newspapers and signed by the "Cookie Monster" was sent to a local newspaper.

The sender demanded that a shipment of cookies be sent to to a local children’s hospital. "The ones with milk chocolate, not the ones with dark chocolate or without chocolate," the letter read. 

And should the request not be fulfilled? "The golden cookie would be sent to the trash can of Oscar the Grouch," the ransom note warned.

An accompanying photo showed someone dressed up as the famous "Sesame Street" character taking a big bite from a golden cookie.

Investigators are unsure whether it is the actual metal cookie missing from Bahlsen or just a hoax. "The ransom note and the photo have been forwarded to criminalists for investigation," a police spokesman in Hannover said.

Police have received only one other tip: Witnesses reported having seen two men with a ladder working at the statue two weeks ago.

Experts say the theft of the cookie could be connected to rising thefts of metal across Germany, as the value of bronze, iron and other metals has gone up significantly. In recent years, thieves have stolen electric cables, bells and even train tracks in Germany and other European countries.

So far, there are only crumbly clues in the investigation, but the company has offered the equivalent of more than $1,300 for any information leading to the recovery of the historic golden cookie.

Company boss Werner Bahlsen made a public appeal for the return of the cookie in a Wednesday news conference, adding, "We refuse to be  blackmailed."