Shocking pictures of Syrian children killed by barrel bombs or drowned in the Mediterranean are "just touching the tip of the iceberg", an award-winning British filmmaker who has documented a refugee family's plight has warned.
Sean McAllister's new film A Syrian Love Story follows opposition revolutionary Raghda and her husband Amer as they are forced to flee Syria with their children, first to Lebanon and then to France.
The documentarian said the atmosphere at screenings ahead of its release had changed after pictures of three-year-old Syrian refugee Aylan Kurdi's body on a Turkish beach rocked the world.
Mr McAllister told the Press Association: "It's a strange thing, a few bodies swept up on a beach has brought the exile and refugee out of the view of the 'enemy' and into the world of compassion.
"The pictures are upsetting but they should be shown, they are not offensive.
"What's more offensive is seeing a boy's head decapitated because of a barrel bomb dropped by Assad. The actual reality of what's going on is much more depressing than those images.
"I think we need a wake-up call and that's just touching the tip of the iceberg."
Following his experiences making the film - which included being detained by pro-government forces - Mr McAllister accused the West of burying its head in the sand over Syria.
And he described David Cameron's pledge for Britain to take in up to 20,000 Syrian refugees over the next five years as "pathetic".
He said: "I think we should get real. We can carry on putting our head in the sand and thinking that we are doing something by taking a few thousand.
"But unless we all start seriously addressing it and allowing certain channels and passages for people to move down it's going to become more and more of a problem."
Mr McAllister was blindfolded, bundled into a car and locked up in October 2011 by forces loyal to Syrian dictator Bashar Assad while making his film.
He was taken to what he describes as a "torture chamber" for a week where he witnessed a 24-hour cycle of beatings, although he was not harmed himself.
A Syrian Love Story won the Grand Jury prize at Sheffield Doc/Fest in June, while Mr McAllister's 2005 film The Liberace Of Baghdad was awarded a special jury prize at the prestigious Sundance Festival.
It will be in cinemas and on BFI Player from Friday and on BBC Storyville later this month.