Justice Secretary Robert Buckland tweeted he was “shocked and saddened” by the news.
He said: “My thoughts are with the officer’s loved ones, colleagues and the wider police community.”
Steve Reed, Labour MP for Croydon North, said his thoughts were with the officer’s family and colleagues.
He tweeted: “All of us in Croydon are in shock at this heartbreaking tragic news.”
Sian Berry, Green candidate for Mayor of London added: “This is shocking and really sad news. Our public servants take risks every day on our behalf, but this kind of incident should not come with anyone’s job. No-one should lose their life at work.”