Taliban gunfire and a roadside bomb wounded four Canadian soldiers and an Afghani interpreter in two separate attacks west of Kandahar on Monday.

One soldier was hit by gunfire while a roadside bomb blast wounded three others and their interpreter. The attacks occurred just minutes from each other in the volatile Zhari district, where Canadian forces have often come under Taliban fire.

Initial reports had said the bomb hit a vehicle carrying the soldiers, but according to CTV's Paul Workman, the military now says the troops and the interpreter were on foot.

"They have been doing more foot patrols in the last while," he told Â鶹´«Ã½net on Monday afternoon. "It was either a land mine somebody stepped on or it was remotely detonated when the soldiers were passing."

All of the injured were transported from the field to the NATO hospital at the Kandahar Air Field.

Workman said one of the soldiers is in serious condition and will be flown to a U.S. military hospital in Germany for treatment before returning to Canada. The three others will be treated at the base, he said.

The attack comes after a week that has seen the Canadian forces increase their efforts to break up Taliban bomb-making operations, dubbed Operation Rolling Thunder. During the operation, Canadian troops killed a Taliban sub-commander identified as Mullah Tohr Agha, as well as 16 fighters.

The Taliban fighters who attacked the Canadians on Monday were likely retaliating after those deaths, said Maj. Jay Janzen, an army spokesman.

"We've come to expect retaliation from insurgents following their setbacks and we do everything possible to ensure we are prepared,'' Janzen said, adding the injured interpreter was transferred to an Afghan army hospital.

The last Canadian soldier to die, Cpl. Michael Starker, was killed in the Zhari district.

In recent weeks, Taliban fighters have increasingly engaged NATO soldiers directly. Previously, they had preferred to use explosives. Of the 83 Canadian soldiers who have died in Afghanistan, 39 were killed by buried bombs.

With files from The Canadian Press