HELSINKI (AP) — A wolf that captured international attention earlier this year after being rescued from an icy Estonian river by construction workers may have been killed, authorities said.

The Environment Agency told local broadcaster ERR late Wednesday the wolf’s GPS tracking collar hasn’t transmitted signals for a week.

Estonian lawmaker Peeter Ernits, who is outspoken on environmental affairs, said on Facebook the wolf had “probably” been shot east of Tallinn, some 200 kilometers (124 miles) from where it was found in February. He cited the ongoing police investigation on the matter.

The exhausted ice-coated young wolf was rescued from the frozen Parnu River in southwestern Estonia by workers who initially mistook it for a dog.

It was released back to into nature with a tracking collar after it had recovered in a shelter.

The wolf was about one of about 200 estimated to roam in Estonia. The grey wolf was voted Estonia’s national animal by nature organizations last year.

The three construction workers on the Sindi dam who saved the frantically swimming animal from a maze of ice in April received the “Hero to Animals” award from PETA, the U.S.-based animal-rights organization.