Philip Seymour Hoffman mourned at funeral in New York

Cate Blanchett and Amy Adams were among the guests at the funeral

Friends and family of actor Philip Seymour Hoffman have paid their respects at a funeral in New York City.

Among those at the Church of St Ignatius Loyola were Meryl Streep, Cate Blanchett, Ethan Hawke, Spike Lee and other show business figures.

The Oscar winner was found dead at his home in Manhattan on Sunday with a syringe in his arm.

While police believe Hoffman, 46, died of a heroin overdose, a post-mortem examination was inconclusive.

The New York City medical examiner's office has said more tests are needed to determine what exactly killed Hoffman.

Authorities also found dozens of bags of what seemed to be heroin in the actor's apartment.

Hoffman's partner of 15 years, Mimi O'Donnell, and their three children walked behind the coffin as it was brought into the church on Friday.

Playwright David Bar Katz, who found Hoffman's body, looked visibly upset as he arrived before the funeral.

Mimi O'Donnell, former partner of actor Phillip Seymour Hoffman, holds her daughter Willa as she touches the head of their son Cooper as the casket arrives for the funeral of actor Hoffman in the Manhattan borough of New York, 7 February 2014Reuters

"We are devastated by the loss of our beloved Phil," Hoffman's family said in a statement

The lights at theatre marquees on New York's Broadway, the centre of American theatre, were dimmed on Wednesday in Hoffman's honour, and a candlelight vigil was held outside the Labyrinth Theater Company. His close family held a private wake on Thursday.

A larger memorial service is being planned for later in February.

Amid the investigation into the actor's death, three people have been arrested on drug charges, including one on a charge of heroin possession with intent to sell.

Lawyers for all three deny the suspects had anything to do with Hoffman's death.

Hoffman had previously spoken about his struggle with drug addiction. After 23 years of sobriety, he reportedly checked himself into a drug treatment programme for 10 days last year after relapsing in 2012.

Filmmaker Andrew Upton, left, and his wife Cate Blanchett arrive for the funeral of actor Philip Seymour Hoffman at the Church of St. Ignatius Loyola 7 February 2014AP

Filmmaker Andrew Upton and actress Cate Blanchett arrive at the funeral

Actress Meryl Streep arrives at the Church of St. Ignatius Loyola for the private funeral of actor Philip Seymour Hoffman 7 February 2014AP

Actress Meryl Streep, who was nominated for an Oscar alongside Hoffman for the 2008 movie Doubt, was among mourners

Spike Lee attends the funeral service for actor Philip Seymour Hoffman at St Ignatius Of Loyola 7 February 2014Getty Images

Spike Lee, who directed Hoffman in the film The 25th Hour, arrived early at St Ignatius Of Loyola

Actor Joaquin Phoenix (L) arrives for actor Philip Seymour Hoffman's funeral at the Church of St Ignatius Loyola in New York on 7 February 2014Reuters

Actor Joaquin Phoenix (left) arrives for the funeral

David Bar Katz, centre, a friend of actor Philip Seymour Hoffman, arrives for the actor's funeral at the Church of St Ignatius Loyola in New York on 7 February 2014AP

Playwright David Bar Katz (centre), who discovered Hoffman's body, also attended

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