A record number of Londoners fled the capital in 2018, new internal migration figures reveal, with an economist blaming the exodus on violent crime and the cost of living.

An Office for National Statistics study of internal migration — not including figures of migrants coming from outside the UK — published Wednesday found that more than 340,000 residents left London to move to other regions. The rise represents the highest number since the ONS began collecting these statistics seven years ago.

In the year to June 2018, 340,498 Londoners left the city while just 237,270 migrated inwards from the rest of the country, representing a net loss of 103,228. The numbers join a growing trend, with 336,000 Londoners leaving in 2017, with both figures notably higher than the first recorded internal migration figures in 2012, when 255,140 people left.

Reasons for Londoners moving elsewhere, with the most popular destination being the south-east of England, include wanting to live in a cleaner environment, cheaper homes, and better schools, but also, as Christopher Snowdon, head of lifestyle economics at the Institute of Economic Affairs (IEA), noted, to get away from London’s violent crime.

While saying that property prices were “a big deal” and a contributing factor, he added in comments reported by The Times: “Obviously people also want a better quality of life. But they also want access to good schools, to live in rural areas and to get away from the stabbings.”

‘Khan Is a Disaster’: Trump Says London ‘Needs New Mayor ASAP’ After Three Killings in 24 Hours https://t.co/L35ZE2sCe2 — Breitbart London (@BreitbartLondon) June 15, 2019

According to the House of Commons library, in the period of 2017 to 2018, 168 knife offences were committed per 100,000 people in London, the highest proportion in England and Wales. In April, the ONS revealed that knife crime was at its highest since records began, with knife crime at its highest anywhere in the country in London.

One Wednesday night, an 18-year-old man was stabbed to death in West London, and is the latest victim in a series of homicides with the city seeing five killings in six days earlier in June. After the city had faced three murders in just a 24-hour period, U.S. President Donald J Trump weighed in and condemned London’s mayor Sadiq Khan for losing control of the capital, calling Mr Khan a “disaster”.

The violence has become so extraordinary in the city, that media reported on Wednesday a stabbing attack against a donkey that had been retired after 20 years of giving children rides around Blackheath. The 28-year-old donkey had been found bloodied in his paddock in south-east London on Friday after having been stabbed three times. He was taken to a veterinarian for treatment and is recovering. The animal’s owner believes he may have been targeted as part of a “sickening” gang initiation.

However, while internal migration is at a net negative in London, external immigration — foreigners coming to London for the first time from outside the UK — and London birthrates have been on the rise. The ONS notes that “four local authorities with the fastest-growing population were all in central London”: Tower Hamlets, Camden, Westminster, and the City. The report adds that a “cluster of central London boroughs hav[e] the highest levels of net international migration in the year to mid-2018”.

London’s population, currently at 9.1 million, is set to hit the 10 million mark by 2029. The growth is being driven by immigration with around 172,000 international immigrants arriving in the capital annually. The rate of arrivals for just London annually is higher than the failed 100,000 target for the whole country the governing Conservative Party promised voters in three consecutive elections.

The ONS figures also revealed that across the United Kingdom, immigration grew the population to 66.4 million, while births fell two per cent to a 12-year low of 744,000.