Toronto Mayor David Miller has decided to lower City Hall's flag to half-mast, in recognition of the four Canadian soldiers killed in a bomb attack in Afghanistan over the weekend.

"Tomorrow the flag will be lowered to half-mast between 7-7:30 a.m.," spokesperson David Ross told CTV.ca on Monday.

The decision comes amidst a controversial choice by Ottawa to leave flags at normal station above the Parliament buildings.

The four slain soldiers include Toronto-native Cpl. Matthew Dinning, Cpl. Randy Payne, Bombardier Myles Mansell and Lieut. William Turner.

They died Saturday when a roadside bomb detonated under their lightly armoured G-Wagon jeep as they travelled from Gumbad to Kandahar -- a journey of about 75 kilometres.

They were returning from a goodwill mission to a northern village.

Their bodies are being flown back to Canada, and are tentatively expected to arrive at CFB Trenton, Ont., between 6 p.m. and 7 p.m. on Tuesday.

More than 3,000 coalition troops, including Canadians, Americans, Britons, Australians, Dutch, French, Romanians and Estonians, lined the runway for Monday's send-off ceremony at Kandahar airfield.

With a bagpiper solemnly in lock-step behind them, pallbearers took the four caskets up the ramp of a waiting Hercules transport aircraft for the flight home.

"Into your hands Lord, we humbly entrust our brothers," intoned Captain David McLeod, a Roman Catholic padre with the Canadian Forces.

"In this life you have raised them with your tender love. Deliver them now from every evil."

Flag debate

Outside coalition headquarters in Kandahar Monday, the Canadian flag flew at half-mast, while the government defended its choice not to lower the Parliamentary flags.

In a letter to The Globe and Mail Sunday, Defence Minister Gordon O'Connor said his government is returning to a tradition that the Peace Tower flag is lowered only once a year, on Remembrance Day.

"The previous Liberal government broke with this long-standing tradition ... and instead decided on an ad-hoc basis to lowering the flag of the Peace Tower," O'Connor wrote in the letter.

"As Minister of National Defence, I can tell you that this adhockery unfairly distinguished some of those who died in Afghanistan from those who have died in current and previous operations."

Fifteen Canadian soldiers and one diplomat have died in Afghanistan since 2002.

An investigation has been launched into this latest attack.

With files from The Canadian Press