Police said that a major tragedy was averted by good fortune in the city's posh Clifton area when the remote-controlled improvised explosive device (IED) aimed at a van carrying the 11 Chinese workers failed to detonate.
Police said the IED had been planted in a flower pot at a roadside in Boat Basin in Clifton.
"The target was apparently a vehicle carrying some Chinese workers which was escorted by rangers and passed through," one officer said on condition of anonymity.
He said the bomb disposal squad had been called in immediately to ensure there were no other IEDs around.
Police also discovered some 11 homemade bombs in a shop which was damaged after one of the IEDs went off accidentally in the afternoon.
"It was a Kabari (junk) shop and after the minor explosion took place it was partially damaged. More search yielded 11 home made bombs from the shop whose owner is under investigation now," an official said.