Marcin Kania
Marcin Kania (inset) drowned during a stag holiday in FormenteraDavid Sim/Facebook

A Citibank trade described as "respected" by the firm has drowned while on a stag holiday in the Mediterranean. He was 27.

Marcin Kania, a foreign exchange options trader based in London, got in trouble after swimming off the coast of Formentera. He and a group of friends had been reportedly drinking heavily before hiring a sailboat, local police said.

His friends raised the alarm when he failed to return to the boat. His body was discovered washed ashore on June 6 along the Playa de Cavall d'en Borras, according to a police spokesman.

Lifeguards tried to revive Kania using a defibrillator and paramedics soon arrived on the scene, but he was pronounced dead shortly after.

Police ruled out foul play but admitted alcohol could have played a role in his death.

"Drugs we don't know – as that will take longer to confirm," a spokesman told local media.

A post-mortem has been carried out but the cause of death is not known as of press time.

Chirag Patel, a managing director and head of foreign exchange flow options at Citi, led tributes. "Marcin was a rising star in the business and I am privileged to have managed him over last few years," he said.

"He had a strong work ethic, was dedicated to his job and was an integral part of the team."

A Citi spokesman added: "Marcin was a great team member and was very well liked and respected. He will be sorely missed. Our thoughts are with his family."

According to his LinkedIn.com page, Kania traded "vanilla options" for euros, Swiss francs, pounds and Scandinavian currencies and used to volunteer at the British Red Cross.