(Photo by Jeff Motz/KFOR News)LINCOLN–(KFOR Jan. 9)–A mechanical malfunction on a semi-truck hauling pool chemicals outside of Lincoln Northwest High School on Wednesday afternoon prompted a hazmat response from Lincoln Fire and Rescue. According to LFR, this prompted the closure of NW 48th and West Holdrege Street. LFR officials say a chemical leak of hydrochloric acid happened as it was being unloaded. The driver apparently thought they saw a small fire start and used a fire extinguisher to put it out. The leak was contained and the Health Department responded and has been working with a private company for clean up. Students were kept inside Northwest before they were allowed to be released, once it was considered to be safe. Below is a message sent out to Northwest parents from Principal Cedric Cooper. Northwest Falcons, Thank you for your patience and understanding as we handled the situation after school today. I wanted to provide you with follow up information as we prepare to have classes tomorrow. We have been informed by the Health Department that it is safe for us to have classes as normal tomorrow. We need students who walk to school to avoid the east loop area. Students may enter through Door 1, or through Door 18 as they normally do. Lincoln Public Schools Operations team will be working through the night to clean up the area, and will remain on site tomorrow morning to address any other concerns should they arise.  Now that we have more information about the incident, I want to let you know what we know: At approximately 3:45 p.m., a company that we contract with had an accident inside their trailer, causing a chemical reaction. This chemical reaction caused smoke, but there was no fire as initially reported. Some of the chemicals inside the trailer did leak onto the pavement of the driveway. At no time were there any chemical leaks inside the building. Everything happened outside. Once we became aware, we pulled everyone inside the building and called Lincoln Fire and Rescue.  We then initiated our Standard Response Protocol of Secure. A Secure means we keep all students inside and monitor the entrances. We shut down our air handling systems out of an abundance of caution. Under the direction of emergency responders, it was determined to be safe for us to initiate a controlled release of students to the South side of the building as everything was happening on the North and East side of the building, with the wind coming from the South. We did not receive any reports of students or staff experiencing ill effects.  The Health Department and Lincoln Fire and Rescue monitored air quality inside and outside of the building.  We appreciate the quick response by Lincoln Fire and Rescue, the hazmat team, and the health department. We also appreciate our students and staff for remaining safe, respectful and responsible and following instructions.  Please contact the school if you have any other questions.   Cedric Cooper Principal