The driver of a cab who jumped a Market Street curb and struck two bystanders might have been on the phone at the time of the collision, one witness says — but in a preliminary report, the San Francisco Police Department suggests that a medical issue affecting the driver might be to blame for the crash.

The 59-year-old driver of what police say was a four-door Ford Fusion Yellow Cab jumped the curb at Market and Sutter Streets at 3:17 Tuesday, striking "a public bathroom, a newsstand and then hit the shoe shine stand" according to an SFPD report.

Two people were injured when the driver struck the shoe shine stand: The 66-year-old shoe shine strand owner identified in various media reports as Saleem Bae (ABC 7) or Mohammed Salim (CBS 5) and a 40-year-old homeless man who worked as his assistant, identified by CBS 5 as "Jazz."

The driver was also injured in the collision, and all three were transported to San Francisco General Hospital in critical condition. As of Wednesday morning, according to a spokesperson with SF General, the driver has been released from the hospital, Bae (that name used here for the sake of expediency) had been upgraded to fair condition, and Jazz's condition remained critical.

According to witnesses who spoke to ABC 7, the cab was "flying down Market Street" before the collision, with one saying that the driver was "was going very fast."

Speaking with NBC Bay Area, one witness wondered just how fast the cab was going, given the amount of damage to the area.

"How are you going so fast to knock something over?" she asked. "A couple years ago, a bus hit that and only dented it."

Witness Rita Tripp, who was at the scene of the collision, told CBS 5 that the driver "told me he was on the phone, with his friend,” when he jumped the curb.

In a preliminary report from the SFPD, however, they write that the driver "was having a medical issue when he hit the gas and drove up onto the sidewalk."

SFist's efforts to contact Yellow Cab for comment and clarification on the issue have not been successful as of publication time, but spokesperson Bob Cassinelli issued a brief statement to KRON 4, saying that “At this time our thoughts are with the injured people."

Sources within the SFPD tell SFist that police were at the collision site until late Tuesday investigating the incident, and are seeking surveillance video from area businesses. CBS 5 also reports that "The entire crash was captured by surveillance cameras on a nearby Muni bus." The footage captured by the bus camera, police say, is now in the hands of investigators.

Update: In a press release sent to media Wednesday afternoon, they write:

On August 23, 2016 at approximately 3:17 PM, a taxicab travelling westbound on Market Street left the roadway and jumped the curb at Sutter Street. The taxicab struck a shoeshine kiosk on the sidewalk and two pedestrians at the kiosk were injured. The driver- a 59 year-old male from Burlingame- remained at the scene and is cooperating with the investigation. He was later treated and released from a local hospital. The pedestrians- a male in his 60’s and a male in his 40’s- remain hospitalized with life-threatening injuries. The San Francisco Police Department’s Traffic Collision Investigation Unit (TCIU) is handling the investigation. Impairment does not appear to be a factor and investigators will be conducting a thorough examination including: driving history, possible mechanical issues with the vehicle and possible medical conditions of the driver. The cause of this incident is yet to be determined. Investigators are examining evidence including surveillance video of the area. Anyone with information regarding this investigation is asked to contact the SFPD Tip Line at (415) 575-4444 or Text a Tip to TIP411 and begin the text message with SFPD.

Previously: Three Seriously Injured After Taxi Jumps Curb In FiDi