A third suitcase containing human remains has been recovered from a toxic lake in Cyprus this week as police continue their investigation into an army captain who has confessed to killing at least seven women and girls.

Cyprus police spokesman Andreas Angelides called Tuesday’s discovery a “major development” in the ongoing investigation into the case that has shocked the nation.

The case came to light on April 14 when the bound body of Mary Rose Tiburcio, 38, from the Philippines, was discovered by chance down a flooded shaft near the toxic lake that was part of what is now a disused copper mine.

CYPRUS POLICE WIDEN SEARCH AFTER SUSPECTED SERIAL KILLER ADMITS HE MURDERED MORE WOMEN

Cyprus Special Disaster Response Unit and investigators transport a suitcase from a boat after it was retrieved from a man-made lake near the village of Mitsero, outside of the capital Nicosia, Cyprus, Tuesday, June 4, 2019. (AP Photo/Petros Karadjias)

A second woman's body — thought to be that of Arian Palanas Lozano, 28, also from the Philippines — was found in the mineshaft a few days later.

An unidentified 35-year-old army captain was arrested in connection with the deaths after investigators found that he had online communications with the first victim.

He reportedly confessed to seven killings in all in a 10-page handwritten note.

CYPRUS SERIAL KILLER CASE FOCUSES ON SEARCH FOR SUITCASES IN MURKY WATERS OF TOXIC LAKE

Cyprus Special Disaster Response Unit investigators carry a covered suitcase on a stretcher after it was retrieved from a man-made lake near the village of Mitsero, outside of the capital Nicosia, Cyprus, Tuesday, June 4, 2019.  (AP)

He led them to where he disposed of the bodies, including a dry well in a military firing range where the remains of who is thought to be Ashita Khadka Bista, from Nepal, were found.

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Tuesday’s discovery marks the third suitcase containing a body retrieved from the lake following a six-week search.

Police continue to search for the body of Tiburcio's six-year-old daughter in another lake where the suspect said he disposed of it.

The Associated Press contributed to this report.