Domestic violence has risen dramatically in London in the past seven years, figures show, prompting concern about the hidden problem of “widespread sexual violence” in the capital.

It comes as the London mayor, Sadiq Khan, announces an extra £15m of funding for support services for domestic violence victims, saying cuts had left them at “breaking point”.

Data shows there was a 63% increase in domestic abuse offences between 2011 and 2018. In the year ending March 2011, there were 48,422 domestic abuse offences recorded by the Metropolitan police, compared with 78,814 up to the same point in 2018.

The figures were in published in a report released by the Mayor’s Office for Policing and Crime. They show that in the past year, three-quarters of victims were female and those who experienced domestic violence were more likely to live in more deprived areas. Earlier this month, it was revealed the number of killings in London linked to domestic abuse trebled from nine to 29 in 2018.

Joan Smith, the chairwoman of London’s Violence Against Women and Girls board, said: “The public has yet to realise how widespread sexual violence is.”

Khan said he was “appalled” by the findings. “The number of people killed by someone they knew in our city is shocking … Support services in the capital do an amazing job, but the funding situation has left them at breaking point,” he said.

“Victims, some of the most vulnerable people in our society, are often having to wait a long time for help.”

Figures show funding for women’s services fell 50% in 2017 as demand rose by 83%. While 15% of all recorded sexual offences take place in the capital, only 6% of government funding comes to London, leaving services at crisis point, according to the report.

Khan wrote to the home secretary, Sajid Javid, this week, asking the government to play its part and reverse huge cuts to the sector, as well as increase police funding.

The report estimates 246,700 adults aged 16 to 59 who live in London have experienced some form of domestic abuse. Women are more likely to have experienced domestic abuse than men (5.9% compared with 2.9%).

Marai Larasi, the executive director of Imkaan, a black and minority ethnic women’s organisation, said: “Violence against women and girls continues to affect thousands of us across London and we need urgent, widespread change at every level. This can only happen if this becomes a priority for enough of us.”

Sarah Green, a co-director at the End Violence Against Women Coalition, said: “We hope Sadiq’s renewed commitment to ensuring support and protection for abuse survivors, and tackling perpetrators, will make our city one of the best places to grow up as a girl, and live as a woman.”

Last year, government figures showed domestic violence victims were waiting almost two years on average to receive compensation for abuse. The Ministry of Justice said its most recent statistics show it takes an average of 612 days, or about 20 months, for a payout from the Criminal Injuries Compensation Authority.

Nearly two-thirds of referrals to support services between the end of 2017 and the summer of 2018 were unsuccessful. Rape crisis centres across the capital have been regularly forced to close their waiting lists and, for the first time in the middle of 2018, all four centres shut their lists due to demand.

Sara, a survivor of domestic abuse, said: “During the years I struggled with low self-esteem as a result of years of abuse. I was moved around a lot but wasn’t able to find the help I needed. I was eventually placed in a Solace refuge where they supported me to rebuild my life. If only I’d had this support earlier, I might have been able to avoid some of the abuse. Now I can finally see a future, a life ahead of me.”

The Home Office has been approached for comment.

• In the UK, the domestic violence helpline is 0808 2000 247. In Australia, the national family violence counselling service is on 1800 737 732. In the US, the domestic violence hotline is 1-800-799-SAFE (7233). Other international helplines can be found at www.befrienders.org