The first Female infantry Officer is set to join the ranks of the Marine Corps according to service officials in a statement released on Thursday. This is a historic achievement as the Marine Corps has never admitted a female officer in its 250-year history.

On Wednesday, according to the statement, the female lieutenant alongside her male colleagues completed a three-week combat exercise, which was the final graded requirement in their 13-week course.

The Marine Corps is regarded to have the toughest training in the military, where almost 25% of those who enlist do not complete the entire course. Out of 36 hopefuls who had attempted the course, she will be the first female to complete it and will lead a platoon of 40 infantry Marines once she graduates.

Female resistant

The Marine Corps is regarded as the most resistant unit to full gender integration in the military. This year, the military service was rocked by a scandal involving over 1,000 veterans and Marines, who were investigated for sharing nude pictures of female colleagues online.

As part of an effort to make the military fully inclusive, the Obama administration lifted the barriers inhibiting women recruits about two years ago, so that they could be included in the service.

Graduation

Sources who are privy to the graduation, but who requested to remain anonymous, told NBC News that it would take place on Monday. The ceremony will include a "warrior breakfast," at the Quantico Marine training base in Virginia.

What remains between now and graduation day is a few administrative tasks and returning the equipment used for training.

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Marine Corps officials did not give the name of the lieutenant and were scanty about her details.

The anonymous military sources also said that it was highly unlikely that she would do any press interviews as she preferred to do her job professionally and quietly.

Attempts

Since the Pentagon opened the doors to the military for women in 2015, a total of four female Marines have attempted the course. The figure includes the female lieutenant graduating on Monday. One of the four attempted the course twice, but she still was not able to complete it.

The course consists of strength, endurance and stamina training, with officers required to carry up to 152 pounds of weight around, for long periods of time.

On the first day of training, a grueling endurance test is taken to ensure combat preparedness and weapon assembly, coupled with long hikes through the hilly and wooded grounds of Quantico. Most of the time, 10% of the trainees drop out on the first day.