Alternative payment provider Dwolla Inc. was the victim of a distributed denial of service (DDoS) attack that brought down its website late last week.

The attack was first reported by, a division of AOL Inc.

Jordan Lampe, a Dwolla spokesperson, said in an email Monday that the attack, which consisted of a surge of traffic to its Internet service provider created by automated visitors known as “bots,” overloaded its website, making it unavailable for users to access their accounts.

“We have no reason to believe any of Dwolla’s core systems, account information, or user funds were affected,” Lampe said.

Dwolla, which was launched in 2010 by entrepreneur Ben Milne, offers a peer-to-pay payment system that allows users to exchange funds over a secure network and provides retailers with a lower priced alternative to credit and debit card processors.

According to a timeline on a blog site maintained by Dwolla, the company’s website went down Wednesday afternoon and was restored by about 3 p.m. Friday afternoon.

Due to the structure of the Internet, there is no definitive way to wholly prevent such an attack, Lampe said. Several other financial services companies that are much larger than Dwolla, among them Wells Fargo & Co, were also subject to denial of service attacks recently.

“Along with our providers, we’ve implemented specialized vendors and processes to help better deter events like this in the future,” he said.

In posted comments on its Twitter page, several Dwolla account holders complained the outage made it impossible for them to use Dwolla to buy bitcoins, a virtual currency, through bitcoin exchanges such as Mt. Gox. That exchange was also subject to a DDoS attack on Thursday, Fox Business News reported.