A convicted bank robber, under heavy guard, gave damning evidence yesterday against his alleged partners.

"I gotta do what I gotta do,'' surprise witness Yusef Ameerbakka DeSilva told the Supreme Court jury hearing the trial of Rupert Elroy Archibald and Michael Eugene Dillas.

The two men are charged with two counts of armed robbery, and carrying and using firearms in connection with the armed robbery of the Bank of Bermuda in Somerset on April 9 last year.

At least seven extra officers -- two of whom wore conspicuously baggy tops over waist level bulges suspected to be guns -- were on hand to escort DeSilva into court.

DeSilva appeared in regulation prison wear of bright orange trousers and a white T-shirt. He is currently serving an 18-year prison sentence in connection with the failed robbery.

As he took the stand, DeSilva looked straight at Archibald and Dillas as he pinpointed them as part of the gang.

But the 28-year-old repeatedly hung his head, smiled to himself, or sighed as he spoke.

Neither Dillas nor Archibald made any visible reaction throughout the damning testimony.

According to DeSilva, he, Archibald and Travis Dill -- who has not appeared before the court -- met at Dill's house at Bob's Valley, Sandys Parish on the Wednesday before the robbery to organise the raid.

"My role was to go in the bank and secure the guard, get him to lay down on the ground,'' DeSilva told Crown counsel Brian Calhoun.

"Roy (Archibald) was supposed to come in after and secure the doors, the customers and any motion.

"Dill was to come in after and go over the counter and into the drawers.'' And on the following Monday, the three men went to Somerset to examine the bank's surroundings and their proposed escape route.

The men met again on Tuesday to further discuss their getaway, said DeSilva.

After leaving the Somerset dock in a rented Boston Whaler, the robbers planned to drive to Jews Bay, then up a Tribe Road and pathway to Archibald's girlfriend's house on Lighthouse Hill.

The entire robbery was planned from start to finish, but DeSilva said on the morning of the incident he was surprised to find Dillas waiting at Davis' house.

"Both of them (Archibald and Dill) told me he was there to watch the bikes outside the bank so nobody would take them away or trouble them,'' he said.

DeSilva said he was chosen to rent and prepare the escape boat and meet back with the others later in the morning.

And he also said he went to two supermarkets to buy a black nylon stocking for Archibald to wear over his face and gloves to protect their hands from gunshot residue.

DeSilva also explained that he wore a double layer of clothing on the day of the crime because: "You don't want to be running around in the same clothes when you rob the bank.'' And he gave a detailed description of the clothing worn by his alleged accomplices.

DeSilva then continued to give testimony of his actions after he entered the bank's main door.

"I pointed the gun at the guard and told him to move,'' he said. "I cocked it and said it again.

"Then I looked over my shoulder, and those guys weren't there. Actually I was going to run away from the bank because I got a little timid at that time.'' However, DeSilva said he soon found the other men outside and then he, Dill and Archibald burst in.

Convicted bank robber turns on his alleged accomplices "I hopped over the counter and started emptying the drawers, Dill was already over the counter emptying the drawers.

"Roy (Archibald) was doing what he was supposed to do -- he was securing the area.'' And DeSilva went on to say the single shot fired by Archibald was planned in advance.

"That was just to shake everybody up and let everybody know we mean business...by the time the shot went off, everybody else was out of the way.'' But once outside, the original plan changed, DeSilva explained. The robbers had decided to pair off on motorcycles and escape along different routes to the waiting boat. The abandoned motorcycles were supposed to be placed out of sight.

However, DeSilva said the two cycles travelled in the same direction and the men left the bikes exposed in their haste to board the boat.

As they sped across the Great Sound, the men thought they had made good their escape, DeSilva added.

But moments later, he said he saw a fast moving boat take off in their direction.

"My instinct told me that it was the Police,'' he said.

Although the well-prepared robbers had a Police scanner with them, DeSilva said it was never turned on.

After throwing their gloves overboard, the gang once again changed plans when they saw Police units stationed some 200 to 300 yards away from their original landing point.

DeSilva said he instead steered the boat straight into rocks near the Riddell's Bay Golf Course and everyone waded ashore.

The men then dashed across a private yard and onto a road below the club house. At some point in the dash, Dillas -- who had been holding both the guns while on the boat -- handed the weapons over to DeSilva.

DeSilva claimed he then threw both guns into bushes and ran off after he saw Archibald and Dillas run away together in a gap in the trees, and Dill apparently throwing the money bag away.

All the men were eventually arrested.

Yesterday, DeSilva admitted to the nine-woman, three-men jury that he hoped his testimony would help his pending court appeal.

"I don't want to be up there (Westgate Correctional Facility), regardless of what I did,'' he said.

And he went on to say he felt a greater obligation to his four-year-old daughter than to his alleged former accomplices.

After DeSilva's testimony, both Archibald Warner and Victoria Pearman -- representing Archibald and Dillas, respectively -- made lengthy submissions for a one-day trial adjournment.

The defence lawyers argued that they needed time to consult their clients, conduct further investigations and possibly interview more witnesses.

"I had no idea Mr. DeSilva would be giving evidence,'' said Ms Pearman.

"This would be trial by ambush, and that is not permitted by law,'' she later added.

And Mr. Warner said DeSilva's "surprise evidence'' was inconsistent with prior evidence.

Chief Justice Austin Ward adjourned the trial until this afternoon and ordered DeSilva be placed in protective custody.