Indonesian authorities have seized nearly 700 endangered pig-nosed turtles at the main airport serving the capital Jakarta, an official said Monday.

The turtles, which were less than a month old, had been transported from the easternmost province of Papua to Soekarno-Hatta airport on a local carrier but their final destination was unknown, said quarantine official Teguh Samudro.

"We don't know where they were being sent as the address on the package does not exist," the official said. The turtles would be released back into their native habitat in Papua soon, he added.

The 687 pig-nosed turtles, a species distinguishable by its fleshy snout-like nose, arrived at the airport on March 15 but officials did not know who had sent them.

Under Indonesian law, the offence carries a maximum three-year jail term and a fine of 150 million rupiah ($15,406).

Pig-nosed turtles are listed under the Convention on International Trade in Endangered Species, which imposes international trade restrictions to protect species from over-exploitation.