NORMAN, Okla. (CNN) – Two people are in custody after more than 1,200 pounds of liquid methamphetamine were found in the diesel tank of a semi-truck in Norman, police officials confirmed.

According to police, officers assigned to the 21st Judicial District Attorney Drug and Violent Crime Task Force conducted an investigation Monday morning on a semi-truck in the parking lot of a hotel in the 100 block of 26th Avenue SW.

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Through the investigation, officers located 1,262 pounds of liquid methamphetamine in the passenger side diesel tank of the semi-truck. The estimated street value of the drugs seized is $4.4 million, according to police.

Police said the seizure is one of the largest ever to occur in Oklahoma.

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The semi-truck driver, 36-year-old Enrique Lara of Chicago, Illinois, and its passenger, 21-year-old Jasmine Morales of McAllen, Texas, were arrested on a complaint of aggravated trafficking and booked into the Cleveland County detention center.

The incident remains under investigation.

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