Four climbers were killed in separate climbing accidents in the French Alps on Tuesday.

Two Italian women, aged 37 and 41, were killed by an avalanche as their climbing party tried to summit Mont Blanc du Tacul in the Mont Blanc range.

The Italian climbers were swept away when a slab of snow came loose on the Face du Tacul early on Tuesday morning.

The climbers had set off for the summit from the Cosmiques refuge, at an altitude of 3,600 metres at 2am, before being hit by the avalanche.

According to regional newspaper Le Dauphiné Libéré, a specialist team of mountain rescue police set off on foot from the town of Chamonix at 4am to search for the missing mountaineers.

A helicopter, carrying another rescue team, was also sent to aid efforts at 8am.  In all, 20 gendarmes, five firefighters and five mountain rescue guides were involved in the search.

Dauphiné Libéré reported that rescuers were faced with the threat of further avalanches, meaning the search operation was restricted, with only one person able to work at a time.

The newspaper reported that the climbers' rope was located before a desperate dig for survivors was undertaken. However later in the morning French gendarmes confirmed the deaths ofthe tow Italians.

Their guide however was pulled from the snow alive but is in a serious condition in hospital in Annecy. A fourth climber was also missing after the avalanche and a search wasstill  underway. The rest of the party appeared to have escaped unharmed.

“The three climbers were buried in a crevasse,” an officer from the gendarmes told Dauphiné Libéré. “This is a very busy time of year in this sector. There was maybe 40 people on the ascent at the time of the accident. The area is still very unstable," the officer added.

The was more tragedy in the Alps on Tuesday when it was reported that two French climbers were found dead in a 20 metre-deep crevasse on the Roche de la Muzelle, at 3465 metres of altitude in the Ecrins massif.

Mountain rescue services in the Isere region said the couple, described as "amateur climbers", had left a refuge on Monday morning and appeared to have fallen into the crevasse on their descent from the summit.

The woman was identified as a 51-year-old from the southeastern French city of Chambery. No further details were provided about the man's identity.

Below is a map where the accident took place. 

Thousands of tourists flock to the French Alps annually for sports including mountain climbing and skiing, but every year some fall victim to accidents.

Mont Blanc, the highest peak in western Europe is considered one of the most dangerous mountains to climb but that does not stop around 20,000 attempting the summit each year. Around 500 make the top each day during the summer.

A number of  mountaineers already have already lost their lives this year.

Only last month The Local reported how a police training exercise on Mont Blanc ended in tragedy when three climbers from the French gendarmerie plunged 1,000 metres to their deaths.

And earlier this year a father and son from Britain were killed on Mont Blanc when they fell near the Bossons glacier.

Last year saw one of the deadliest summers ever on the slopes of the mountain when nine were killed in an avalanche near Mont Maudit, a satellite peak of Mont Blanc.

Climber Jason Smith highlighted the dangers of trying to summit France's highest peak after scaling the mountain himself earlier this year.

"Having just returned from the summit of Mont Blanc on 2nd July, and a trip across the Aiguille, it seems so sad but inevitable that these accidents will always happen regardless of safety steps, due to the nature of the mountain and weather," Smith said.