One person was treated for minor injuries after a public transit bus dropped into a sinkhole in downtown Pittsburgh on Monday morning.

Extracting the Port Authority bus out of the sinkhole is expected to take hours as authorities wait for a crane to arrive on scene, according to Pittsburgh Public Safety. The bus was waiting at a red light in downtown just before 8 a.m. local time when the back end fell into the sinkhole along with a Kia Optima.

A woman, the single passenger on board, was treated for minor injuries and released from a local hospital, authorities said. The bus driver appeared to be safe and unharmed.

"We are grateful for ⁦@PghPublicSafety⁩ and that no one was seriously injured," the port authority said. "We’re being told a crane needs to be brought in to remove the bus and it will be several hours before it can be extracted. Detours in the area will likely remain in place the remainder of the day."

The cranes will have to remove the bus after power is shut off to three power lines directly beneath the bus, according to NBC affiliate WXPI. Pittsburgh Public Safety Director Wendell Hissrich said workers will be unable to strap the bus to a crane before the lines are turned off.

“(The) problem that we’re experienc(ing) is that we have to lift that Port Authority bus straight up because we have a Duquesne Light electrical vault involved and we have several gas lines involved and we don’t want to create any further problems."

It will likely take up to four hours to assemble the 300-ton crane and another hour to set it up for it to remove the bus.

Hissrich told reporters that the cause of the sinkhole is still unknown and won't be determined until after the bus is removed. He estimated that the sinkhole is between 15 to 20 feet deep.

"From what I see, it's not going to go deeper, but the front end of the bus may fall if the land starts caving in in front of the bus and that's what we're concerned about," Hissrich said. "I mean, it is a deep hole."

The street could be closed for up to two weeks as crews work on construction, depending on whether the power and fiber-optic cable lines were damaged. Verizon and Comcast explained that if the cable lines under the were sliced or damaged it could impact communications throughout the tri-state area, Hissrich said.

Comcast is the parent company of NBCUniversal, which owns NBC News.

A children's day care nearby was evacuated to a Westin hotel in downtown, but no one else has been evacuated. Some businesses may have power or water turned off later as crews continue to work.

Traffic in the area might be shut down for up to 10 hours, which may impact people traveling to the Monday night Pittsburgh Steelers game against the Miami Dolphins. Hissrich said authorities were working with the Westin hotel, which was expecting about 400 guests for the game.

CORRECTION (Oct. 29, 2019, 3:15 p.m. ET): A previous version of this article misspelled the name of the Pittsburgh public safety director. It is Wendell Hissrich, not Hissirch.