Meryl Streep, Cate Blanchett and Julianne Moore were among the mourners at Philip Seymour Hoffman's funeral in New York City today (07.02.14).

Approximately 400 of the late actor's friends and family members, including his mother, Marilyn O'Connor, his estranged partner Mimi O'Donnell and the couple's three children, Cooper, 10, Tallulah, seven, and Willa, five, gathered for the private service at St. Ignatius Loyola Catholic Church in Manhattan.

An eyewitness told PEOPLE.com that Mimi, who reportedly kicked Philip out of their home a few months ago in an act of ''tough love,'' arrived with their children in a black SUV and followed 10 pallbearers carrying the casket into the church at the stroke of noon.

'Amazing Grace' could be heard from inside the church as the casket was removed and placed in the hearse following the 90-minute ceremony.

Laura Linney, Justin Theroux, Anna Paquin, Ethan Hawke, Amy Adams, Ellen Burstyn, Spike Lee, Michelle Williams, Joaquin Phoenix, Louis C.K., Mary-Louise Parker, John Slattery, John C. Reilly, Jerry Stiller, Brian Dennehy, Marisa Tomei, director Joel Coen, Justin Long, Diane Sawyer, Mary-Kate Olsen and boyfriend Olivier Sarkozy were also spotted outside the church.

The Oscar-winning actor was found dead in his home in the city last Sunday (02.02.14) after an apparent heroin overdose.

The star of 'The Hunger Games' and 'Capote' reportedly fell off the wagon in 2012 after being sober for more than 20 years and he entered rehab in May 2013.

He was allegedly found with around 70 bags of heroin inside his apartment after Mimi sent his friend David Bar Katz over to check on him when he failed to show up to see their children.

A larger memorial service is in the works for later this month.