A national crime agency officer has told a jury of the moment law enforcement agents boarded a tug suspected of drug smuggling.

Alan Carruthers, who is based at the Scottish Crime Campus in Gartcosh, North Lanarkshire, was giving evidence at the trial of nine Turkish men who deny smuggling and being involved in the supply of cocaine in April 2015.

The tug, MV Hamal, was searched in Aberdeen and 129 bales of cocaine were found in a ballast tank at the front of the ship.

On Tuesday, the High Court in Glasgow heard Mr Carruthers was ordered to fly to Stornoway in Lewis and board the Royal Navy warship HMS Somerset.

He was part of a team which set off on a rigid inflatable boat (RIB) from the warship in international waters around 11am on April 23 to board the Hamal.

Another RIB set off from the UK Border Force cutter Valiant at the same time.

The court heard the tug was located after being searched for by the warship, the cutter and a spotter plane.

Mr Carruthers was asked by prosecutor Ashley Edwards what his role was and he replied: "I was to detain the crew and oversee the initial search of the vessel."

Miss Edwards asked: "Was there information that drugs might be on board?" Mr Carruthers replied: "Yes."

Mr Carruthers was asked what he saw as he approached the Hamal and said: "There was no activity on board."

He said he made his way to the bridge and discovered Mumin Sahin, the captain, and Emin Ozmen there.

The court heard the crew were assembled in the mess area and told they were being detained and taken to Aberdeen.

Mr Carruthers told the court that as the ship headed back to Aberdeen harbour the satellite phone began ringing at around 7.45pm.

He added: "There were five or six calls from the same number over the course of 30 minutes."

Mr Carruthers said he ordered the captain not to answer the calls and took a note of the number.

The court heard the captain was cooperative and helped with translating what was happening to his crew.

The 129 bales of cocaine were brought to the court last week to show the 14 jurors the amount of drugs recovered.

Kayacan Dalgakiran, 64; Mustafa Guven, 48; Mustafa Ceviz, 55; Umit Colakel, 39; Ibrahim Dag, 48; Sahin, 46; Ozmen, 51; Abdulkadir Cirik, 32, and Muhammet Seckin, 27, are on trial accused of being involved in an international drug-smuggling operation.

It is alleged they smuggled cocaine from Istanbul in Turkey via Tenerife in the Canary Islands, Spain, to South America, and then to the North Sea between February and April 2015.

They are further alleged to have been concerned in the supply of the class A drug between April 21 and 23.

They deny the charges against them. The trial, before judge Lord Kinclaven, continues.