HAMPTON, Va. (WAVY) — The search for missing four-year-old Codi Bigsby is on its fourth day as Hampton police and the FBI continue to explore new leads and expand their search efforts.

Click here to subscribe to WAVY’s breaking news email alert

On Wednesday, the missing 4-year-old’s father, Cory Bigsby was been named a person of interest. During a press conference, police said he had willingly been at the police headquarters since Monday and was cooperating with officers.

Thursday night, 10 On Your Side learned Bigsby had been charged with seven counts of child neglect. The charges stem from incidents dating back to December.

Attorney Jeffrey Ambrose confirmed to 10 On Your Side’s investigative team that he has been retained to represent Cory Bigsby, but that he had not been able to meet with him as of Thursday evening. Ambrose said that he went to the Hampton Police Division in person to speak with Bigsby, but was declined access to him. Police told Ambrose that Bigsby had not requested an attorney, according to the lawyer. Ambrose was directed to contact the Commonwealth’s Attorney’s Office.

Hampton Police Sgt. R.C. Williams told 10 On Your Side that he could not confirm if Bigsby has requested or retained an attorney.

The expanded search efforts included support from neighboring fire and police officials. On Thursday, the Cape Charles police and Suffolk firefighters joined the search in Hampton.

In addition, police are working with 50 volunteers each day to help aid in the search. As they look through the search area, police are also asking the public to provide any information they can.

Police once again visited Codi’s home on Thursday afternoon.

Anyone who has seen Codi, his father or siblings since Christmas is asked to call the FBI at 1-800-CALL-FBI. Those who live in their apartment complex, Buckroe Pointe, and have surveillance cameras are also asked to call the FBI.

Below is an interactive timeline of the search for Codi:

Police say Codi Bigsby was last seen in the 100 block of Ranalet Drive, at the Buckroe Pointe townhomes in the Buckroe area of Hampton.

Officers were called to the home just after 9 a.m. on Monday, January 31. When they arrived Codi’s father told them the child was last seen around 2 a.m. Authorities said the family is continuing to cooperate with the search.

Codi Bigsby is about 3 feet tall and was last seen in all black clothing and Spider-Man flip-flops.

Those who have information about where Cory Bigsby would go, shop or do are asked to contact Hampton police. People who live in the Old Buckroe neighborhood are also asked to check their property and alert police if they see or saw anything suspicious.

In addition, police say they continue to search within a one-mile radius of the apartment complex where Codi lives. While the search radius has not changed, they are expanding their search areas within the grid.

All waterways within the grid are being considered for the search.

Hampton police investigators returned to the home on Ranalet Drive Thursday afternoon to gather additional evidence. Evidence technicians came out with several sealed bags at 3:45 p.m., returned to the home and brought out more evidence. Uniformed officers continued to stand outside the entrance to the two-story townhome at 5 p.m.

People came from all over to help find Codi. The community is hoping for the best as a fourth day of searching for the 4-year-old continues in Hampton.

Mary Thompson said she came out to help look because she didn’t want the community to lose another baby with their life ahead of them.

“I’ve been out here ever since the search started. And I lost two sons myself so when I heard about little Codi, I wanted to come out here and support our community,” Thompson said.

Army veteran Michael Christian said he felt horrible when he heard the news about Codi’s disappearance and knew he had to come out and help look for him.

“I was scared for the little, for the little fella. Umm, I just want, I want him back home safely and sound… with his family and his friends and, you know, live his life. He’s only 4 years old. He still has a whole life to live,” Christian said.

They searched with the help of three other volunteers and a Hampton police officer.

Even if you can’t come out and look — there are still ways for you to help.

“If y’all have ponds or whatever, go out there on the edge of the water and just search your yards and stuff. Search your grills, any kind of opening that you have connected with your houses,” Thompson said.

“When you’re driving in the road, look on the side of the road. See if you see anything out of the ordinary. If you’re walking, just look around. That’s all you have to do. Open your eyes. Think big, think wide, anything can help,” Christian added. “I’ve been going through sewer wells, jumping fences, going into backyards, looking underneath everything. Just to find at least an article of clothing that he could be wearing or a tip in helping to search for him.”

You can sign up to volunteer on the Hampton police social media pages.