A Maplewood woman who responded to an online advertisement promising to fix her computer was swindled out of more than $90,000. She was one of five victims who were collectively scammed out of more than $180,000 during July and August in financial exploitation cases that have police in the east metro city warning residents to be on guard.

“Whether these cases represent a broader national trend or a random local uptick in fraud case reporting, the result is equally disturbing,” said Maplewood Police Chief Paul Schnell. “In some instances, the victims lost nearly all their life savings as a result of these scams.”

The crooks used a variety of tactics and schemes to gain trust with the victims and coerce them to comply with their demands, Schnell said.

In the case of the woman caught up in the computer scam, the victim paid a $249 service fee, then was told that her computer was being hacked. The scammers told the woman that someone had deposited money that did not belong to her into her bank account and that if she did not return the money police would come and arrest her. She paid the scammer more than $90,000.

In another case, a victim was told she won a large sum of money in a Canadian lottery, but had to pay processing fees before she could collect the winnings. The scammer told her to surprise family members, so she didn’t tell anybody until she had lost $28,000.

A third resident was taken for $7,000 in what’s called the “Grandparent Scam.” In that scam, a caller pretending to be a grandchild or another family member claims they need money immediately, often for a legal or medical emergency. The scammer tells the victim to deposit money in secret account or on a card and to keep the transaction a secret.

Other cases involved a person going door to door collecting fees and promising to return later to do yard work or perform handyman services and a Nigerian charity scam in which victims are tricked into sending money, computers and cellphones to an international scammer. Victims lost $48,000, $28,000 and $6,250 respectively.

“Those committing these crimes develop a complex web of lies and deceit that make it very difficult for victims to sort out the truth,” said Maplewood Police Detective Ryan Parker. “By the time victims understand what’s occurred, they may feel embarrassed that they were exploited financially.”

Many times, the crimes go unreported because victims don’t want others to know they fell for a scam. And when they are reported, detectives have difficulty catching the perpetrator and recovering the money because the crimes often cross state lines or are carried out from overseas.

“It’s easy to think a scam could never happen to us or those we care about, but it could,” Schnell said. “We only hope that bringing these cases to public attention reminds us of the wisdom of the old saying, ‘trust but verify.’ ”

The Maplewood Police Department offered these tips to recognize scams:

• Don’t send money to individuals outside the United States if you have not met them in person

• Set social media privacy settings to limit information available to others

• Hang up on “robocalls”

• Don’t trust caller ID; scammers make phone numbers look official

• Don’t give out personal information or money without talking with somebody trustworthy.