Related Clues

• Alert
• Caution
• Tip off
• Raise a red flag
• Put on notice
• Give an alert
• Give a heads-up
• Alert to danger
• Serve notice
• Premonish
• Advise caution
• Give notice to
• Yellow-card
• Honk at, perhaps
• Give a heads-up to
• Notify in advance
• Give an alert (to)
• Threaten
• Put on guard
• Shoot off a flare, e.g.