Explanation

Pakistan conducted a series of  nuclear tests on  28 May 1998  at the  Chagai  test site,  in  Balochistan.

5 Nuclear  tests were  conducted  by Pakistan  at 15:15 hrs PST on 28 May 1998.

The tests were performed at  Ras Koh Hills  in the  Chagai District of Balochistan Province.

Chagai-I  was Pakistan's  first public  test of nuclear weapons.

while

Chagai II

Chagai-II is the  codename assigned  to the  second atomic test  conducted by Pakistan, carried out on 30 May 1998

These  tests followed  the  Chagai-I series

The  test site was  Kharan Desert , Pakistan

The  number  of tests is  1