Officials have increased security ahead of Friday’s first free practice for Sunday’s Bahrain Grand Prix.

An increased police presence was visible along the 30 kilometre route from the capital Manama to the Bahrain International Circuit, while the number of road-blocks had also increased.

Pro-democracy protestors calling for reforms have called for demonstrations outside the entrance to the track for Thursday afternoon.

Formula One team Force India decided not to compete in the second free practice session on Friday due to security concerns as they wanted to be in their hotel before sundown.

Team official Bob Fernley confirmed to the BBC that the team had decided to leave the track early.

The team was involved in an incident late Wednesday, when their hired car was stuck in a traffic jam and a petrol bomb exploded nearby.

As a result, two members of the team decided to return home.

Last year’s race was twice called off due to demonstrations, but the sport’s controlling body FIA decided that the country was stable enough this year to go ahead.

A growing number of human rights organizations, as well as politicians have criticized this decision.

Clashes between demonstrators and officials occurred again on Thursday night.

“Over the past two weeks we have documented an increase in the number of injuries, arrests, and home raids by police,” said Mattar Mattar, a leading opposition figure within the ranks of opposition grouping Al-Wefaq.

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