The quake-devastated Haitian capital Port-au-Prince has returned to calm after a strong aftershock on Wednesday morning.

The tremor measuring 6.1 on the Richter scale jolted Port-au-Prince at 6:03 a.m. local time (1103 GMT) on Wednesday and was the strongest one after last week's 7.3-magnitude quake in Haiti.

In spite of this, the aftershock did not cause any major new destruction or slowed the ongoing aid work.

But it still aroused panic among residents in Port-au-Prince, who have not recovered from last week's powerful quake.

Witnesses said that when the quake occurred, people ran to the streets and squares, while rescuers tried to direct them.

The epicenter of the quake, with a depth of 9.9 km, was located 60 km west of the capital, the U.S. Geological Survey (USGS) said.

The USGS said Wednesday's aftershock was strongly felt in the southern city of Jacmel, which the international humanitarian aid has failed to reach due to the destruction of the highway linking it to Port-au-Prince.

Only the navy of the Dominican Republic, Haiti's neighboring country, has managed to send medicines and food to Jacmel by sea.

Last week's earthquake has killed 75,000 people and injured 250,000, according to the Haitian government. However, the figures may rise as the rescue work continues.