The shilling fell to 90.30/40 at the start of trading from the previous day's close of 90.20/30 as news of the overnight attack broke out. Kenya has suffered a string of gun and grenade attacks since it sent troops into Somalia to fight Al-Shabaab in late 2011.
The attacks have hit tourism industry, putting pressure on the shilling because tourism is a key source of foreign exchange. Gunmen raided Korome quarry overnight while workers were sleeping in tents near Mandera town, close to where Islamist militants shot dead about 28 non-Muslims on a bus last month. "People thought it is bad news for the currency but we have seen it correcting back to 90.15/25," said John Njenga, a trader at Commercial Bank of Africa.
(Reuters and agencies )