Facebook will be fined $662,900 for its failure to protect users’ data, Britain’s Information Commissioner’s Office (ICO) said on Wednesday in its progress report of an investigation on whether such personal information had been misused by political campaigns during the 2016 referendum on the UK’s membership of the European Union. The data regulator said Facebook violated the country’s data protection act by failing to safeguard personal information of its users and maintain transparency on how users’ data were harvested by others. ICO’s head Elizabeth Denham said data analytics firms that help campaign groups to connect with individual voters should follow rules and be open and fair. During the investigation, ICO found that an app had been used to harvest the data of tens of millions of Facebook users by the now-defunct UK-based Cambridge Analytica in the 2016 US presidential campaign and in Brexit referendum. The watchdog will seek criminal prosecution against SCL, the parent company of Cambridge Analytica.