E-scooter start-up Skip is temporarily pulling its fleet from the District, Arlington and Alexandria, after the District Department of Transportation suspended its operations permit Wednesday in the wake of another fire involving its equipment and revelations of two previously undisclosed fires.

The action was prompted by a fire late Tuesday at the company’s D.C. warehouse, the second in a month involving Skip equipment in the city. Upon further investigation, DDOT officials said they learned Wednesday of two additional scooter fires, one in September and another in November. They notified Skip late Wednesday to remove its scooters from city streets within 24 hours.

“DDOT’s priority is to maintain the safety of the public space and will continue to monitor the situation over the coming days,” the city transportation agency said in a statement. The suspension requires that all Skip branded vehicles are removed from the public space in the next 24 hours.”

Skip said it was complying with the city order to temporarily suspend service, but it expects to get its scooters back on D.C. streets soon.

“This was not an issue with scooters in the field, either deployed or charging,” Skip said in a message to riders Wednesday night. “We are fully cooperating with authorities to ensure a speedy and responsible return to DC.”

Skip’s permit allows it to deploy up to 720 scooters in the city, but it’s unclear how many the company has in service. The company started the year with a permit that allowed 600, but it was granted an expansion of 120 in April.

Officials in Arlington and Alexandria, where Skip also operates, said the company was in the process of removing the devices from their jurisdictions Thursday. In San Francisco ―the only other market where Skip operates ― officials with the San Francisco Municipal Transportation Agency said the company notified them of the issues in D.C.

“We will closely monitor the situation as we move forward with our program here in San Francisco,” SFMTA spokesman Paul Rose said.

Eric Balliet, an Arlington County spokesman, said once the scooters “are corrected” the county will have to review and re-approve the company’s participation in its scooter program. Alexandria spokeswoman Sarah Godfrey said the city will review its agreement with the company once it is ready to redeploy.

Skip pulled its scooters from D.C. streets for a few days after a scooter burst into flames in downtown Washington on May 30, but it resumed operations June 6. While the cause of that fire was not identified, D.C. officials said Tuesday the scooters had been outfitted with additional safety features, including tamper-resistant battery cages, that they said would help prevent a repeat incident.

The fire late Tuesday at the company’s D.C. warehouse renewed the concerns about the safety of the devices that have become a popular option for commuters and tourists to get around the city. DDOT said that it has suspended the company’s permit for at least 30 days, but it’s unclear when and under what conditions the city will allow Skip to resume operations.

Skip announced this week’s fire in a tweet.

“Our DC warehouse experienced a limited fire which investigators believe to be started in a bin of removed batteries,” the company tweeted. “This was not a scooter fire and it was not a charging-related fire.”

The company said it is working with experts to expedite the disposal of used batteries. The storage bin contained batteries removed “as a result of the proper operation of Skip’s quality control process,” the company said.

D.C. fire officials on Thursday confirmed three fires at Skip’s scooter facility on K Street NW since the fall, including this week’s. The first, on Sept. 28, involved a scooter being charged. The incident was ruled accidental. The second, on Nov. 22, also involved a scooter, according to dispatch notes, but investigators were not called to the scene.

After the May 30 incident — where a scooter caught fire near 14th and I streets NW in front of a Compass Coffee shop — Skip said that it thought it was an isolated case and that its other scooters were safe to ride. D.C. fire and company officials said that fire appeared to have started around the battery pack while the scooter was parked.

This week a DDOT spokeswoman said Skip did not “conclusively identify the cause” of the fire but discovered a number of “risk factors” and took steps to address them. DDOT, which regulates the shared e-scooter services, did not explain what those factors are and referred questions to the company.

“Before Skip’s scooters were redeployed, DDOT required the company to implement new safety measures that mitigate the risk of a repeat incident,” DDOT said in a statement Tuesday. “As part of the safety protocol, Skip installed tamper-resistant battery cages and monitoring systems on all scooters and will visually inspect each vehicle before it is redeployed. DDOT will continue to monitor performance to ensure the public’s safety. ”

An electric scooter caught fire in downtown D.C.

Skip said this week that it redeployed its scooters on June 6, after a “thorough investigation” and after taking extra measures to prevent scooter damage. But it did not provide details about those new safety measures, nor did it respond to questions about what could have caused the fire.

"We have added additional fleet management features in our software to help guard against intentional and unintentional damage, which the investigation found to be the probable cause of the incident,” a company statement said.

Experts say extra protection for the batteries could be helpful as exposure to dents and shocks, which could happen due to frequent drops, or to extreme temperatures can contribute to overheating.

“The scooters can be engineered to withstand many conditions, but it is difficult to cover or anticipate all possible problems,” Virginia Tech professor Louis Madsen said. For example, frequent dropping of a lithium battery can disrupt the alignment and cause it to overheat more. But a fire in one scooter from an entire fleet is probably no cause to worry, as it could just be the work of one faulty battery, Madsen said.

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The May 30 fire prompted the company to temporarily pull its scooters in the District and San Francisco. It also led to questions about the safety of the devices, which have made headlines in recent months as more people report injuries from riding them. The San Francisco Examiner reported that another Skip scooter caught fire at the company’s San Francisco warehouse in December, just two months after the company launched service there.

Skip’s competitor, Lime, one of the world’s largest scooter companies, pulled its scooters out of service last year after discovering that a number of them may have been carrying batteries with the potential to catch fire.

Skip is one of six companies operating e-scooters in the District.

Teddy Amenabar contributed to this report.