On Saturday afternoon, a massive DDoS attack hit BitGo, a service that describes itself as the most secure Bitcoin wallet solution available today.

The attack lasted between four and five hours and brought down the company's servers completely. BitGo didn't react to the incident until an hour later, tweeting out apologies to its clients.

Usually, Bitcoin users have to wait hours before a Bitcoin transaction is approved. Over the past few years, BitGo has built a ground-breaking and extremely secure platform for powering near-instant Bitcoin transactions.

BitGo DDoS takes down several other services

Because of its unique offering, the service has gathered quite a following in the Bitcoin world, either through its own wallet service or via its API, integrated with companies such as Wirex, Bitstamp, Bitfinex, Unocoin, and Kraken.

These services integrate BitGo in order to provide immediate Bitcoin transactions without requiring users to wait hours for the operation to go through.

As soon as the DDoS hit, many of these companies faced issues as well, not being able to provide immediate resolutions for some of their transactions.

Recently, Wirex has integrated BitGo as the go-to solution to power its Bitcoin-based debit cards. The DDoS attack on BitGo brought down its service, and the company sent out an email message to all of its customers telling them to avoid making transactions until they received confirmation from BitGo that its service resumed.

DDoS attacks on Bitcoin sites are a lucrative business

DDoS attacks on Bitcoin portals is nothing new. Some hackers make a living just from renting their services on the Dark Web and then launching on-demand DDoS attacks on Bitcoin payment portals.

Besides DDoS attacks, Bitcoin services have been at the heart of numerous security-related incidents that have often ended in Bitcoin theft. Some of the services that have recently seen data breaches include Gatecoin, Shapeshift, CoinWallet, BitQuick, Cryptsy, and LoanBase.

BitGo customers - We apologize for the issue, but we're under DDOS attack at this moment. We're working on it and will keep you updated. — BitGo (@BitGo) June 4, 2016