When did the blasts hit the hotels?

ISTANBUL, Turkey — Near-simultaneous explosions hit two Istanbul hotels early Tuesday, killing two people, and another attack unsuccessfully targeted gas tanks at a fuel storage depot. The blasts went off about 1:40 a.m. Seven people were injured in the blasts at two tourist hotels in separate Istanbul neighborhoods. The city’s police chief said the blasts were an apparent terrorist attack.
    Four Spanish men were injured in one of the hotel blasts and went to hospital but none were in serious condition. The men are friends on holiday in Turkey and were staying at the Hotel Star Holiday which was hit by one of the blasts. Two of the Spaniards were "slightly buried" by the debris after the blasts. One suffered two broken legs; the other suffered one broken leg. The two other Spaniards had less serious injuries. The Spaniards were being treated in two Istanbul hospitals, named Cerrahpasa and Haseki. The Spanish government did not release their names or ages, at the request of the injured. The Spanish Consul in Istanbul "is taking care of all necessities" for the injured Spaniards and is aiming to bring them back to Spain as soon as possible. An official, in Madrid, said attempts to establish phone contact with the Spanish diplomatic mission in Turkey had been difficult due to saturated phone lines in Turkey.
    About the same time, attackers tried to use small explosive devices to detonate large fuel storage tanks at the Demiroren Group facility in Istanbul’s Esenyurt neighborhood. The bombs exploded but failed to rupture the fuel tanks. There were no injuries. The first bomb went off about an hour before the hotel explosions, while a second one went off at nearly the same time as the attacks on the hotels.