HILO, Hawaii - Hawaii County Mayor Harry Kim signed a mandatory evacuation order for majority of Leilani Estates Thursday.

The evacuation order means residents within a certain designated area of Leilani Estates must leave or they could be arrested. It also means that if residents in that area call for help, first responders may not show up.

The mandatory evacuation order applies to all residents in Leilani Estates that live east of Pomaika'i Street.

Fissure 8 has been spewing lava up to 260 feet in the air for the past two days. The USGS said it's been the most active of any fissure over the past month. Its flow is 4.5 miles long, the longest flow to date and its front is just under two miles from four corners the intersection of highways 132 and 137. 

There are three fronts to it: the fastest moving of those is the one farthest east. Its moving about 90 yards per hour. Back in Leilani Estates, the fissure continues to feed perched ponds that could break their levees and cause a fast moving flow at any given time. That danger is part of the reason for the mayor's evacuation order.

"You all know the mayor, his abiding concern has always been for the safety of the residents... This is the real reason behind this, the safety of everybody," Janet Snyder, Office of the Mayor, Hawaii County said. 

"A lot has changed since you first went in...Immense changes have happened since we've gone in there. We used to see residence walking in the street, mingling finding out what's going on, talking to the media but today it's like a ghost town which is good because they're taking heed of the warning and doing what the county is asking them to do," Major Jeff Hickman, Hawaii National Guard said. 

Most of Leilani Estates is also covered in lightweight lava rocks that have been shot out and continue to rain down from fissure 8. Sulfur dioxide in some areas are said to have reached deadly levels.

Mayor Kim signed the order at 12:06 p.m., the order went into effect immediately. Residents now have less than 24 hours until possible penalties for being inside. They must be out by 12:06 p.m. Friday. The evacuation order is in place for 60 days or until further notice.