The community is rallying behind a Woden-based disability service provider after vandals destroyed the fleet of cars it uses to transport clients to appointments.
Staff at Koomarri were devastated on Tuesday after arriving at work to see the front windows smashed on four cars parked at their Philip offices.
It came after nearby Woden Community Service's cars were vandalised on Thursday.
It is the second act of vandalism this week in Woden, after arsonists torched a storage shed at Woden Athletics Park on Monday night, destroying about $200,000 worth of athletics equipment.
Koomarri chief executive Nadine Stephen said the cars were used to transport about 100 clients to medical appointments and shopping trips.
"We are devastated," Ms Stephen said.
"It was such a shocking, senseless act and really, it boggles the mind why anyone would want to do this. The offenders might see it as four cars, but for us it affects so many people.
"Our clients are upset and confused, they don't know why anyone would do this."
Ms Stephen said the cars had since been towed, and was unsure if they could be repaired.
She said Koomarri, a non-for-profit organisation that also has offices in Belconnen and Queanbeyan, had been overwhelmed by an outpouring of community support since the attack.
"The community has been so amazing and we've had offers from local businesses and other people to help us out," she said.
Woden Community Service CEO Chris Redmond said the organisation's cars were also targeted on Thursday.
The office is located about 400 metres from Koomarri.
Mr Redmond said the organisation had kept its cars in a public car park for many years without any previous incident.
An ACT Policing spokesman said the offenders had not yet been identified due limited avenues of enquiry.
Anyone with information should contact contact Crime Stoppers on 1800 333 000, or via the Crime Stoppers ACT website.