The manhunt for 65-year-old Pavol Vido had been underway since around 7 a.m. Authorities confirmed that he shot himself just after 2 p.m.
Vido is also accused of shooting and killing secretary, Toni Kelly.
According to Justice of the Peace Ralph Fuller, the second victim, identified as David Grubbs, has also died.
His brother, Chris Grubbs, who was also shot, has since been removed from ICU.
Liberty County sheriff's Deputy Whitten's family says he is in serious, yet stable condition and making progress.
Deputies say Liberty Co. suspect shot himself to death after shooting 4 people
Officials say it all started at B Dependable Plumbing on Highway 321, where 65-year-old suspect Pavol Vido waited for two employees and then shot them.
Vido left the scene and pulled into the parking lot of Big Thicket Veterinary Clinic. Deputy Richard Whitten followed him, and the two got into a shootout.
Deputy Whitten was shot in the throat at a veterinary clinic. He was flown to the Texas Medical Center.
At the time, Capt. Ken DeFoor with the Liberty County Sheriff's Office said Deputy Whitten was alert and responsive.
However, Thursday morning, officials said the deputy is in critical condition due to complications.
SEE ALSO: What we know about deputy injured in Liberty County shooting
Vido left the clinic in a stolen, white 2004 Mercury Grand Marquis with Texas license plate FGZ7180.
Around 10:40 a.m., the vehicle was found about a mile away from the plumbing business on CR 2477.
Liberty County shooting suspect's vehicle found
According to preliminary information from officials, Vido was living in a metal container behind the plumbing business.
In the last month, the sheriff's office served Vido eviction papers.
The people who own the land where Vido was living are connected to the plumbing business, authorities say.
ARMED AND DANGEROUS: What we know about suspect in deputy-involved shooting
Seven Cleveland ISD schools were in lock-in mode due to the shooting investigation.
Tarkington ISD was also on lockdown as a precaution.
Those have all been lifted.
Woman killed, 3 others shot, including deputy in Liberty Co., shooter on the run
The Liberty County Sheriff's Office posted more information about Whitten, who became a deputy in June 2015.
Whitten is a lifelong resident of the Cleveland area. He's been married for 14 years and has two children, who are 22 and 25 years old, the sheriff's office said.
WATCH: Officials give update on how shooting unfolded in Liberty County
Liberty Co. officials gives update on shooting and gunman on the run
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