DUBAI (Reuters) - Bahrain accused Qatar on Monday of illegally seizing three boats with 16 sailors on board, state news agency BNA reported, worsening an already deeply troubled diplomatic situation in the region.

Coast Guard Commander Commodore Alaa Siyadi told BNA the boats were seized over the past three days. The report gave no details on the boats or where they were seized.

Qatar confirmed it detained fishing boats after they entered its territorial waters illegally, and said the sailors will be released soon.

Siyadi said the seizure raised to 15 the number of boats seized, and the number of sailors in Qatari custody to 20, adding that some of the boat seizures date back to 2009, BNA reported.

“All unauthorized fishing boats receive a warning to leave Qatari waters, and if they are non-compliant, they are referred to the competent authorities,” a source at Qatar’s Interior Ministry said. “The crew will be released within three days, while the ships will be detained until the court makes a decision.”

Bahrain, together with Saudi Arabia, the United Arab Emirates and Egypt, imposed diplomatic, trade and travel sanctions on Qatar in June, accusing it of supporting terrorism, which Doha denies.