"As you can see, I am alive," said the 36-year-old in a video posted on Thursday on an Instagram account under her name.
Earlier this week, the Los Angeles Police Department said Banks, known for her roles in the television shows "Gossip Girl" and "Blue Bloods," was unharmed and no foul play is suspected in her reported disappearance, adding that the case was closed.
Additionally, messages were posted that claimed abuse by her family and indicated she had willingly left "to escape my cage."
"Follow my [YouTube] I'll be posting my official interview ... and in the days to come ... answers to ALL of your questions," she wrote in an Instagram story.
After being informed of the LAPD's update, Banks' cousin Danielle-Tori Singh said it was "fake news" and vowed to continue distributing flyers describing Banks as missing. The family plans to host a news conference on Friday.
On Tuesday, Singh told ABC7 that a tip led police to a home in Texas, where a woman came to the door and identified herself as Banks. Police later showed body camera video of the encounter to Banks' family, according to Singh, who said the woman was not Banks, adding that the woman in the footage did not look like the actress did the last time she was seen in a FaceTime call.
Before police said she was found, relatives had reported the 36-year-old actress and Playa Vista resident had not been heard from since late last month.
Authorities conducted welfare checks at her home, and her family said they recently entered the apartment where she had been living with her husband of one year and found her belongings and dog still there.
Singh, who arrived from Toronto to help with the search, said she's very close with her cousin. When even just a few days went by without hearing from her or being able to reach her, she and other family members grew worried.
"Five days without hearing from my cousin is red flags and alarm bells," Singh told Eyewitness News earlier this week. "She doesn't go more than 48 hours without speaking to me or her mom. ... That girl is more like a big sister to me."
(The Instagram account under Banks' name, however, claimed "I have not spoken to Danielle in over 15 years much less every day or 48hrs as they've perjured.")
Singh distributed flyers in Banks' neighborhood. On Tuesday she said Banks' husband had not been cooperating with the family or authorities.
"He's not willing to help LAPD. He's not willing to help me or her mom find her," Singh said. "He is removing flyers off of posts and cars."
Banks' IMDB page lists appearances in shows such as "Blue Bloods," "Twelve" and "Gossip Girl." She at times acted under the name Chanel Farrell.
Singh said her cousin had been moving away from acting in recent years and was focusing on writing.
"I can tell you in my soul, in my gut, something is not right," Singh said on Tuesday. "We're crossing two weeks now without a word, without a sound. Nothing."