npm run start working whereas ng serve not working

问题

I try to run angular 2 app with ng serve in Linux machine. It is not working. But I tried npm run start command. It is working fine. I got the following message when I tried ng serve command.

As a forewarning, we are moving the CLI npm package to "@angular/cli" 
with the next release,
which will only support Node 6.9 and greater. This package will be 
officially deprecated
shortly after.

To disable this warning use "ng set --global 
warnings.packageDeprecation=false".

You have to be inside an angular-cli project in order to use the 
generate command.

I'm trying this command inside the project folder also.

My package.json file as follows

    {
      "name": "xxxxxx",
      "version": "1.0.0",
      "scripts": {
        "ng": "ng",
        "start": "ng serve",
        "build": "ng build",
        "test": "ng test",
        "lint": "ng lint",
        "e2e": "ng e2e"
      },
      "private": true,
      "dependencies": {
        "@angular/animations": "^4.1.3",
        "@angular/common": "4.1.3",
        "@angular/compiler": "4.1.3",
        "@angular/core": "4.1.3",
        "@angular/forms": "4.1.3",
        "@angular/http": "4.1.3",
        "@angular/platform-browser": "4.1.3",
        "@angular/platform-browser-dynamic": "4.1.3",
        "@angular/router": "4.1.3",
        "@angular/upgrade": "4.1.3",
        "angular2-jwt": "0.2.3",
        "chart.js": "2.5.0",
        "core-js": "2.4.1",
        "moment": "2.18.1",
        "ng2-charts": "1.5.0",
        "ngx-bootstrap": "1.6.6",
        "primeng": "^4.0.0-rc.3",
        "rxjs": "5.4.0",
        "ts-helpers": "1.1.2",
        "zone.js": "0.8.11"
      },
      "devDependencies": {
        "@angular/cli": "1.0.4",
        "@angular/compiler-cli": "4.1.3",
        "@types/jasmine": "2.5.47",
        "@types/node": "7.0.22",
        "codelyzer": "3.0.1",
        "jasmine-core": "2.6.2",
        "jasmine-spec-reporter": "4.1.0",
        "karma": "1.7.0",
        "karma-chrome-launcher": "2.1.1",
        "karma-cli": "1.0.1",
        "karma-jasmine": "1.1.0",
        "karma-jasmine-html-reporter": "0.2.2",
        "karma-coverage-istanbul-reporter": "1.2.1",
        "protractor": "5.1.2",
        "ts-node": "3.0.4",
        "tslint": "5.3.2",
        "typescript": "2.3.3"
      }

}

I have tried ng generate module [name]. It also not working gives the same above message. What can be the reason for this?