London, July 20 - Pop star Madonna, whose concert was cancelled after two people died in a stage collapse, paid respect to the victims during her tour in Marseilles in France.

'Let's all just take a moment to say a prayer for Charles Criscenzo and Charlie Prow. Our hearts go out to their family and loved ones,' dailymail.co.uk quoted Madonna as saying.

The singer appeared in a black dress and embraced a widow. She also visited eight workers who were still hospitalised.

'She (Madonna) wanted to make a positive gesture. She won't be performing but will be showing solidarity with the victims' families. She is moved by what happened and feels very personally involved,' a source said.

Explaining the unfortunate incident, a stadium worker said: 'Normally four cranes are used to lift temporary roofs but on this occasion only three were being used. It was a recipe for disaster.'