WASHINGTON, June 23 (Xinhua) -- The U.S. state of New Jersey passed a new law Friday to ban marriages under the age of 18, becoming the second state to do so in a country where child marriage is widely practiced.

According to the new law, marriage will only be allowed between people who are 18 or older, changing the previous legislation which permitted minors as young as 16 to marry under certain circumstances.

"No child should be forced or coerced into marriage," Governor Phil Murphy said in a tweet after signing the legislation, pledging that his state "will be a national leader in protecting the welfare of children."

The state's move was welcomed by lawmakers and activists who have campaigned for more protection for children. State Assemblywoman Nancy Munoz, one of the bill's prime sponsors, said, "Getting this law passed was a long fight, but well worth it."

State Senator Nellie Pou, another sponsor, said it was a moral obligation to safeguard children and prevent them from being forced into marriages.

Despite the state's effort to protect underage children, especially girls, from forced and premature marriages, it remains striking that among all 50 states in the United States, New Jersey is only the second state to pass such a law.

The state of Delaware passed a similar law just last month.

While all states provide that the age for marriage should be 18 or older, the remaining 48 states offer glaring backdoors that allow children to marry under certain circumstances before entering adulthood.

Common excuses for child marriages include either parental or judicial consent or in some cases both.

Considering the exceptions, 19 states do not have a minimum age for marriage, seven states allow marriages for children as young as 14 and 15, meaning that a 15-year-old child can be legally wed in over half of the states, earlier than they can bear arms and drive at 16, or consume alcohol at 21.

Due to varying legislation in different states, little research has shed light on the status of underage marriages across the nation. Incomplete statistics only show the scope of the much ignored phenomenon in the country.

According to estimations by activist group Unchained at Last which advocates against child marriages, approximately 248,000 children were married in the United States between 2000 and 2010, and more than three-quarters of these unions involved minor girls marrying adult men.

A separate data released by the New Jersey Department of Health showed 3,682 minors tied the knot from 1995 to 2015.

Researchers say children marriages unproportionally harm those that are female, poor, and live in rural areas.

According to UNICEF, the United Nations Children's Fund, marrying girls under 18 years old is rooted in gender discrimination, encouraging premature and continuous child-bearing and giving preference to boys' education.

Evidence shows that girls who marry early often abandon formal education and become pregnant. Maternal deaths related to pregnancy and childbirth are an important component of mortality for girls aged 15-19 worldwide, accounting for 70,000 deaths each year, UNICEF said on its website.

The UN agency's warning is lost on staunch defenders of marriages for young children in the United States, who most often find their argument on religious or personal freedoms, citing certain culture or social norms in which children marriages are accepted.

The opposition has undercut common sense efforts to raise the minimum age for marriage in multiple states throughout the years, the New Jersey law was vetoed last year by then governor Chris Christie.

Unchained at Last said that as it prepares to head to Girls Not Brides, an annual global convention against children marriages, later this month, it can "for the first time in history report good news from the United States in the global effort to eradicate a human-rights abuse that destroys girls' lives."