Chris Froome extends Tour de France lead

— -- Chris Froome strengthened his grip on the yellow jersey with a second-place finish as Tom Dumoulin won Friday's Stage 13 time trial at the Tour de France.

Froome showed no ill effects from the chaotic finish to Stage 12 on Mont Ventoux -- when he was reduced to running up the mountain on foot following a crash -- as he finished 63 seconds behind Dumoulin's stage-winning time of 50 minutes, 15 seconds.

The time trial took place in a subdued atmosphere with a heavy police presence following the terrorist attack in Nice on Thursday night.

Dutchman Bauke Mollema was the next-best-placed of the general classification contenders and moves up to second overall, now one minute, 47 seconds off Froome.

Mollema displaced 23-year-old Briton Adam Yates, who had expected to lose time on this 37.5 kilometre test from Bourg-Saint-Andeol to La Caverne du Pont d'Arc, and duly conceded almost two minutes to Froome -- at least less than the four minutes he predicted.

Movistar's Nairo Quintana also lost out, slipping to 2 minutes, 59 seconds off yellow, although the Colombian is still in fourth place.

Twenty-four hours before he crossed the line here, Froome had been caught in a chaotic and bizarre end to Stage 12 on Mont Ventoux when he crashed along with Mollema and former team-mate Richie Porte when a television motorbike was caught in huge crowds on the mountain.

After briefly racing up the mountain on foot before changing bikes, Froome lost almost two minutes -- enough to cost him the yellow jersey -- until the race jury intervened and he came out with an increased lead, 47 seconds over Yates.

It was not known if Froome had suffered any injuries in the incident, but there was little sign of that Friday as he turned in a strong ride to increase his advantage.

After the stage, Froome was joined on the podium by the other jersey holders -- Yates in white (best young rider), Peter Sagan in green (points leader) and Thomas De Gendt in polka dots (King of the Mountain) -- as well as Dumoulin and several Tour officials to pay their respects to victims of the Nice attack.

At least 84 people, including several children, died after a man drove a truck through crowds celebrating Bastille Day along the Promenade des Anglais.

On Friday morning, Tour officials met with police, government, regional and security officials to discuss security arrangements, and Tour director Christian Prudhomme vowed the race would continue "in sobriety and with dignity."

"We wish today to be dignified, in tribute to the victims," Prudhomme said. "We are thinking about the families, we offer our condolences to everyone who has been affected, who has lost a loved one. To everyone who is injured, in flesh and in their being.

"We asked questions of ourselves, effectively. But we think, in agreement with the state authorities, that the race should continue, and we mustn't give in to pressure of people who want us to change our way of life."