QUETTA, 6 June — The government kept a rigid grip on Balochistan province yesterday, searching for any politicians intent on defying an official ban on planned pro-democracy demonstrations. Police confirmed they had arrested a number of members of the 16-party Alliance for the Restoration of Democracy (ARD) based in Balochistan, a sprawling, impoverished province bordering Iran and Afghanistan. But others, anticipating police raids, went into hiding before the authorities began the round-up on Monday, official sources said. They said 49 political leaders had been targeted but only a few of the most senior ones were found. Police were also stationed at the airport and train station in Quetta and other entry points into the province to ensure ARD leaders from outside did not attempt to defy a military government ban on their presence in the province.